‘I’ve seen people die,” Océane said, during one of the online broadcasts she made just before her end. “Frankly that’s not what shocks you. A woman came in to the retirement home where I work and she lasted just two weeks. She arrived and she was fine. I have no idea what shit they gave her: the nurses shot her full of medication. By the end you couldn’t understand what she said, she was mostly dribbling. I remember she said to me, ‘I’m going to die, I’m going to die.’ So I told her, ‘Don’t worry, everything will be OK, I’m here for you, if you want I’ll come and see you in your room.’ The next day I turned up at 8am and she was dead. And what annoyed me the most was they left her the entire day in the room and you had these trainees, these old girls who were like, ‘Let’s go see her, let’s go see her!’ And I said, ‘The dead aren’t a spectacle for your entertainment.’ Then the guy turned up from the morgue and I helped him carry her out.”

Océane was oppressed by the trite and uncaring relations she observed between human beings. She poured scorn on the empty flirtation of social media, their desperate popularity theatre. She had no interest in the artificial animation of alcohol or drugs (though she constantly smoked cigarettes). The dulled existence of the Parisian suburbs, where no one seemed able to engage with anything consequential, depressed her (on the wall behind her as she made her last speech hung a poster with the words NEW YORK PARIS LONDON HONG KONG). “I’m half Turkish and half Polish,” she said, in answer to one of the questions posed by her online spectators. “I don’t understand this mania of always asking people’s nationality. People are always asking: How old are you? What’s your name? Where do you live? What are your origins? People are very very very very stupid around here.”

She lived in a town called Égly. It is a forsaken place, which outsiders rarely visit except to use the regional garbage dump. The street signs speak of decay: the antique shop, the cemetery, the funeral home, the social centre for the homeless. The apartment blocks have white security shutters drawn down over the windows; the noticeboards are posted with instructions for dealing with a terrorist attack (take shelter behind a solid object, turn off the ringer on your phone).

Égly dangles near the end of the Paris-region rail network – the Réseau Express Régional, or RER – which has acquired such a lugubrious grip over suburban existence that it appears constantly in French rap as an image of exclusion and confinement. It is difficult to understand how towns so close to one of the earth’s most significant urban hubs can seem remote until one comes to depend on the maddeningly infrequent trains, which take up to an hour to reach the capital. Then the bleak and denuded landscape makes some sense – and one realises why the jet-setting Parisian elite that runs French business, politics and culture seems so infuriatingly remote and smug. The car-burnings that have become such an emblem of suburban life are very precise, after all, in their symbolism: they are a revolt against the mobile mainstream – against everyone whose rhythms are not drummed out by the deadening stop-start of double-decker trains.

Océane’s relationship with her dispersed family was uneasy, so she did not have the luxury of indifference to the general world. “I don’t speak to my father anymore,” she said. “He’s a jerk.” Océane’s father was a powerful, sensuous individual who took out his moods on the judo floor and the punchbag; his extensive online life indicates a man prosaically impatient with things intangible or far away. He had daughters from two relationships – the two women were not close – but he lived alone, and worried about his fading good looks. He ran a popular nightclub where, in addition to the usual DJ fare, he featured acts such as American Borderline, a frat-boy-and-cheerleader extravaganza including – as his flyer promised – sex toys, strippers, naked teenagers in jacuzzis, strobe showers and many other such marvels, all of it filmed for the American adult media company YouPorn.

In response, perhaps, to such fantasies of youth, 18-year-old Océane was committed to an authentic version of her own. She found something real in the basic act of care; she had completed a diploma in rescue and safety while still in high school, and perhaps her only moment of genuine elan during the two hours of her final broadcasts came when she described her work in the old people’s home, which she found “hyper cool”. She kept a cat, too, which found its way now and then into those broadcasts, rubbing itself against her and purring loudly into her microphone. (“You have a big pussy,” writes one wag, as the cat appears in the frame. “Look out we can see your pussy!” chimes another. By this time, her suicide is only 10 minutes away, and Océane has fallen silent before the dismal stream of commentary.)

France is the country that invented for the west the idea of that transcendental romantic love that would ultimately take over every other kind of soul ambition. This French teenager was far from alone in hoping that the spiritual plenitude the world could not give might be recovered in romance, and indeed she had been in a relationship for the past three years. But she felt unloved by her boyfriend, and unable to find any echo of her deeper world in him. The situation diminished her. She left him, hoping to take her life back. Shortly after that – as she described in her ultimate video address – she met him again, and he subjected her to violent physical abuse. The thin thread broke that tied her to the universe. She entered a living death.

“What would make me happy?” she said, in one of her few protracted outbursts. “Nothing, that’s the point. I’ve got to the stage where nothing can make me happy anymore. I can’t even find the energy to get out of bed in the morning. You realise that one person can completely poison your life. Our relationship completely destroyed me but he can’t understand that because he’s a person with no empathy, I mean the suffering of others doesn’t touch him. You try and do something to improve the situation, to get people to hear you, but it doesn’t work, so … With the message I’m going to send out this afternoon, I hope he’ll finally get it. In this world, unless you shock people, they don’t notice, and it has no effect on anything.”

She spoke unsentimentally of her 19th birthday, which was to arrive three days after her death: “I was supposed to do something this weekend for my birthday. But in the end it’s not happening, I mean I can’t go – because of this thing.”

In the silences, she often sighed, “Je suis trop blasé.” The French word has no implication of superiority: it is only empty, numb, indifferent.

Égly station in the southern suburbs of Paris. Photograph: Christophe Ena/AP

The enterprise of “sending out a message” seems to have given her a renewed sense of energy and purpose. She made a detailed plan, and one that was, as events would show, well conceived. She made it known that she would broadcast some unspecified and sensational event at 4.30pm on 10 May 2016 – using Periscope, a social media app that allows users to stream live video to their followers, who can simultaneously write comments alongside the moving image. She said she would address her followers in two prior sessions on that same day, also via Periscope. Before any of this, she conducted two test sessions to ensure there was nothing she had not thought of.

“The video I’m going to make,” she said, trying to differentiate herself from social media’s general culture of self-promotion, “isn’t designed to faire le buzz. It’s supposed to make people wake up, to open their minds. I want to communicate a message, and I want it to be passed around, even if it’s very shocking.” Her tactic, ironically, was classic social-media princess: schedule a big sensation, and say nothing about what it will be. But she was hopeful that shock could also produce some return to reality. “It’s the only way to communicate a message. The only way left to ensure the message is taken up … Until you provoke people, they don’t understand … But it’s really going to be very, very shocking so honestly I’m telling you that any children watching – and it’s got nothing to do with sex – please leave.”

Océane broadcast for 58 minutes in the morning, and 37 at lunchtime. For most of that time, she sat on her red couch, speaking into the camera, her face more solemn than overwrought – though she rolled cigarettes and smoked them ceaselessly. At one point she walked out of the house to get her mail from the mailbox (a parcel of makeup, the contents of which had been stolen: she showed the eviscerated package to the camera), but otherwise the image did not change. In neither of these sessions did she say what was going to happen, or why; she seemed very much in control of events, and what now looks like apprehension in those videos (“It’s so cold in this apartment. I’m so cold”) did not seem like it at the time.

At 4pm she came online for her third broadcast. She had said she had something to say, and now she said it. She told people that, a few months previously, her ex-boyfriend had raped her and beaten her. Océane gave details of who he was and how he could be contacted. While this was happening, the session started to become chaotic: hundreds of people were joining the feed to see what was going on. Everyone had a point of view: some found her poignant (“The splendour of the world begins with the fragility of a lone woman”), while others took the opportunity to give her spiritual advice (“Convert to Islam and you’ll see everything is gonna be great. Allahu akbar!”). Océane fell silent, reading the scrolling comments and occasionally rolling her eyes. More than a thousand were now watching, and most had missed her message. The mood was raucous: people joked about her appearance and expressed lewd anticipation about what she might do, even as others begged them to stop the stream of comments in the hope she might finish what she was trying to say. Others tried to rouse her from her silence in other ways: “Go on, speak, retard”, or “Show us your tits”, or “I’ve found my dream, a woman who keeps her mouth shut. Will you marry me?”

Océane had retreated behind a persistent smile – the sardonic smile, certainly, of world-despair vindicated by dismal evidence. But it also had a dash of real adolescent triumph: You’re going to regret you ever said those things.

Just before 4.30pm, she took her phone, still broadcasting, went out of the house – leaving her cat for the last time – and walked to Égly’s RER station, which took just a few seconds. As she got close, the mood among her followers began to change:

– This girl has no life, why is she coming to tell her life on Periscope?

– She’s a whore.

– She’s going to kill herself, you’ll see.

– Guys you’re really horrible to say such things. She’s a human being. Your mother or sister could have gone through what she went through.

– Kill yourself.

– The idiot’s going to harm herself.

– Where are you in Égly?

– Where is she going?

– Stop her, she’s going to kill herself.

– Stop that girl.

– This is going to finish badly.

– This feels bad frankly.

– Fuck I think she’s going to jump.

– Don’t jump.

– Yes she’s scaring me!

– Guys can you see the location on her Peri, call the police.

– She’s in despair this chick she’s going to do some bad shit.

– Don’t kill yourself for a guy.

– There’s a train fuck.

– Fucking hell.

– Fuck.

– She jumped under a train.

– RIP.

The suburban train hit her at 4.29pm, right on schedule. After the event, people remembered hearing her cry out, but that may just have been retrospective fancy. Her phone landed lens-down, and showed only black, though the microphone was still recording. Was she dead? Was it a hoax? Minutes went by, and they tried to work out the situation from the murmurs in the background.

– I can hear the firemen.

– She’s not dead.

– I HOPE SHE’S ALIVE.

– Oh fuck this is horrible.

– Let’s pray for her.

– She’s gone too far.

– She gave the number, the address and the FB of her ex.

– They’re gonna cut the feed now otherwise this is gonna blow up.

– It was obvious she was possessed everyone was telling her.

– They’ve found her, guys.

– Cranial coma.

– Show your head dirty whore are you scared?

– Cranial trauma.

At that point the phone was recovered. In the last frame of the feed, a paramedic peered into the screen and pressed the stop button. It was a startling reality effect. But for all those who still believed it was all a hoax, social media users started circulating photographs of the information screens at other stations, which announced train delays due to a death on the line.

Thirty seconds before she killed herself, one of the spectators watching the live broadcast remarked: “Up close, she looks like Nabilla.” Since the video images of those moments were suppressed by Twitter, Periscope’s parent company, it is impossible now to see what it was in her death-mien that would make people think of Nabilla Benattia, France’s kittenish reality-TV superstar. But given her stony demeanour over the preceding few hours, the resemblance seems forced. Indeed, many of the young people congregated for her last addresses found her anything but telegenic. “You’re kinda ugly,” they commented. “Your piercings are gross.” “Dirty whore.” And even – because they were impatient with all the talk, and wanted something to happen, “kill yourself”. “Throw yourself out of the window.”

(As yet, they cannot know how close they aim; indeed she diverts them with false reassurance. “Don’t worry,” she says, still safely installed on her couch, “I live on the ground floor. What am I going to do? Jump into the street?”)

So why, right at the end, did someone glimpse Nabilla in her? Her broadcasts had gone on for more than two hours by then, during which time people had seen her as she was. Avid for specific detail: “How tall are you?” “What piercings do you have?” “Show us your tattoos.” (A heart on her thumb, a red rose on her forearm, which she designed herself. “The tattoos on my stomach I don’t show.”) Why did they stop seeing her, and see someone else in her place?

In the last seconds, spectators had the impression of something foreign and unnerving. “I’m starting to feel her magic inside me,” they said, and it was not quite a joke. “She’s going to put a spell on us.” Some alien spirit had begun to emanate from her – and perhaps it was this new presence, rather than the 18-year-old herself, that reminded someone of Nabilla. Moments from her death, looking into her phone on the platform of Égly station, she aroused a sudden anxiety in her audience – until then so exquisitely blasé. “Can’t you see she’s not fucking human? She’s a ghost. She’s an extra-terrestrial. She’s a sorceress!”

What was this occult shadow they saw late-blooming in the young woman’s face? Was it that curious modern necromancy that had never visited her in life, but which briefly crowned her death, and which – for the very few days her suicide profited the media – she shared with Nabilla Benattia? That hi-tech spirit possession we call, for want of a better word, celebrity?

For a generation so fully embedded in social media, celebrity was not remote or atypical. It was latent in everyone. Schoolgirls debated with each other how they would deal with its burdens – paparazzi, extreme wealth, film-star boyfriends – when they grew up. And this was not surprising. Social media, after all, supplied a publicity machinery with a reach and power previously available only to truly famous people, and now the condition of the celebrity was everyone’s condition. Suddenly everyone was broadcasting their life to the world, and measuring their worth on the basis of the libidinal pulses that came back – as only celebrities had before. Suddenly, the celebrity’s grief over privacy was everyone’s, and everyone was afflicted by her insecurity: do people realise there’s nothing behind it all except my own frail and disappointing humanity?

Océane was wired like everyone else. Like many other teenagers, she had often tried to make her image conform to that of the triumphal media funster: there were images of her on Twitter V-signing in a short skirt and sunglasses on a rooftop in Los Angeles, the Hollywood sign glowing in the distance (“You’re a real film star,” her friends commented, obligingly). This did not stop her being judgmental of everybody else’s online affectations, but that, of course, was the inherent paradox. Surveying the great online pageant of self-promotion and superficiality, social media users were led to believe they were the only ones in the world to have authentic feelings and opinions. “Fakes” was an English word imported by Océane’s French generation, which they used to describe, essentially, everyone other than themselves. On Facebook, Instagram, Periscope, there are only fakes. All the same, there was also no question of opting out. Océane was very much in – she had several Twitter accounts – and even as she railed against what happened on social media, it was on social media that she chose to do it. The only true significance came from mediatisation, and even discontent, if it was to have any meaning, had to be liked and shared.

The problem was that, for the most part, it did not matter how widely broadcast your discontent was: no one cared. The great majority of celebrities – in this new world where even nobodies were celebrities – were lacking in that basic attribute of the celebrity, which was fame. They were half-creatures – unfamous celebrities, anonymous superstars – and unlike their fully-formed counterparts, their thoughts and feelings were lost in the infinite cacophony. This was why there was a constant inflation of strategy and contrivance; for even those whose message was “Authenticity!” found themselves inventing stunts of their own in order for it to be heard.

Since the events that had happened with her boyfriend, Océane’s intimate realm was poisoned. There is no sign that she confided her state of mind to anyone she knew. It was to the broad, anonymous online mass that she decided to unburden herself. But in order for it to mean something, some extraordinary explosion of reality was required. It would have to be of the order of terrorism, which also produced spectacular media effects, and it would probably take her along with it. And so: the macabre theatre of her plan, which transformed her, albeit briefly, into a fully realised celebrity, whose troubled soul was explored in the mainstream news.

There are reasons why the angel of celebrity might have given her moribund figure the face of Nabilla Benattia. Nabilla, after all, was celebrity itself: celebrity in its pure state, uncontaminated by achievement. Five years older than Océane, she had come to prominence on a show called Les Anges de la Téléréalité (Reality TV Angels), where, floating on post-production seraph wings, she revealed herself to be the kind of being that is designed for one thing: faire le buzz (no French woman had more Twitter followers than her). She had a talent for producing deliciously inane aphorisms that so inflamed media and social networks that one had to acknowledge in her a certain kind of contemporary genius. Playing the idiot was a strategy.

French reality TV star Nabilla Benattia. Photograph: IBO/Sipa/Rex/Shutterstock

But there was a dark core to Nabilla, too. She had spent time in jail for stabbing her reality-TV boyfriend in the chest during an argument, and her well-known outbursts of rage seemed to point to profound fears about her own viability. “I’m not doing well,” she wrote to a friend during her assault trial. “I’ve had to give up on certain hopes and I’ve tried to kill myself … Our lives are only passing. I’m weary of it all. I don’t know what to do. I’m at the end.” Is it possible, therefore, that there was a more precise kind of revelation behind that remark: “Up close, she looks like Nabilla”? That it was not just celebrity that was seen unfurling in Océane, but that hidden core of celebrity, which is always-about-to-die?

In the world of social media, where everyone becomes a celebrity, they do not inherit merely the life-force of stardom – its beauty, achievement and sex. What is transmitted also to these faceless ranks of superstars is the inner knowledge of death. For, as all true celebrities discover, the media image feeds parasitically on human energy, starving them and removing them, slowly, from the realm of the living.

In the days following Océane’s death, a wave of people took down their own social media portraits and put up her image instead.

Ten seconds before Océane threw herself off the platform, someone wrote: “She’s strapped herself with explosives, call the police.” It is not surprising that some people, told to expect a sensational event, expected that. It was only 18 months since Amedy Coulibaly, a self-declared member of Islamic State who had grown up not 20km away from Égly, had gone on three separate shooting sprees in Paris the day after the Charlie Hebdo attack. It was just six months since the dark night of shootings and suicide bombings that had killed 130 Parisians, including 89 young people attending a rock concert at the Bataclan Theatre.

But perhaps there were analogies, anyway, between all these happenings. Océane’s death was also intended as a kind of detonation, which would “take out” others apart from herself. On their side, the perpetrators of the Paris attacks were also, let us not forget, bent on their own destruction: they, too, were suicidal. All these people were young, and nearly all of them had grown up in the racialised ghettos of Paris and Brussels. All of them felt some kind of despair about the reality they lived in Europe, and all of them, crucially, decided that the only significant asset they had, in their negotiation with it, was their own existence.

Though we are familiar with the statistics of our monopolistic era, we are far less conversant with its spiritual effects. If mid-20th-century western societies achieved a startling level of consensus, it was due to their extraordinary expansion of the share in the social surplus – to which the destruction (by war) of previous wealth concentrations, and the transformation of “labour” into “jobs”, were essential. Today, as western societies reverse those advances and drift back towards 19th-century arrangements, it should not be surprising that the malaise of that era is returning, too. This malaise is felt most keenly by the young, who have seen nothing during their lifetimes save the progressive re-exclusion of the majority from society’s wealth, and who embark on adulthood with very little hope that they will be able to “make it” as their parents and grandparents did. They have a strong sense, in fact, that now-ageing generations have taken everything for themselves, bequeathing to the young nothing but the burden of their own sins.

Malaise takes on particularly acute forms in the Parisian suburbs, where work has been informalised and automated almost into nothing; in the most depressed areas, a quarter of young women and nearly half of young men are without jobs. But there too, unemployment is only a symptom of the wider casting-out from French society, whose would-be universalism disguises one of the most consolidated power systems in the western world. It is no surprise that the pious messages pasted around these neighbourhoods, which promote the good life of hard work, clean living and happy family – along with the old revolutionary slogan, liberté, égalité, fraternité – are routinely defaced. For some, France itself has become the impediment to any honourable form of life. As one rap group from Océane’s neighbourhood put it, “Dur de rester halal quand des porcs gouvernent” (“Hard to stay halal when the country’s run by pigs”).

This is why the allure of exit haunts dispossessed French youth today. The spread of radical Islam is of course one dramatic expression of this: it is thought that more than 900 young people have left France to go and fight for Isis in Syria and Iraq, and thousands more have joined jihadist networks at home. But militant Islam is spreading among French youth not just through the radicalisation of Muslims, but also through the conversion of non-Muslims, who wish for themselves the activist power it supplies. Those who have turned to Islam in jails, ghettos and gangs represent a significant fraction of France’s estimated 200,000 converts to the faith; a full quarter of those French volunteers to Isis were drawn from these same ranks. It was not, in other words, that they were Muslim, and therefore they wanted to destroy reality and themselves; it was rather that they wanted to destroy reality and themselves – and to rediscover, in the process, some kind of chivalry and nobility – and therefore they embraced the trenchant power of radical Islam.

There are many moments in history when young people have dreamed of glamorous self-destruction rather than embarking, drearily, on adulthood. But those who actually die are the exceptions. Far greater numbers are touched by the same current of despair, but are nevertheless held back from the ultimate act by life’s natural defences. These survivors are not left unscathed, however. They live astride the line between life and death, harbouring a kind of sentimental envy for those who have gone. Theirs is a suicide culture, and they lose some of their ability to identify with those who are simply, and unquestioningly, alive.

A view of Paris’s eastern suburbs. Photograph: Daisy Corlett/Alamy

In the days and weeks after Océane’s death, a number of rap “homages” began to appear online. The rappers were often young men whose unemployment and casual jobs were redeemed by a heroic alter ego – gangster, truth-teller and troubadour – even though, in most cases, their “celebrity” happened in a bedroom, and was known only to themselves. None of them had known the dead girl, but the story of her suicide spoke personally to them. Though their rap voices were gruff with urban aggression, their words were heartfelt and sentimental. “My dearest Océane, these verses are dedicated to you / You’ve gone to be with the angels, what will I do without you?” said one. They wrote about themselves as the tender lovers she never had, and fantasised about having been there to save her.

But there was something dubious about these offers of help made retrospectively to the living Océane. Perhaps it was because, in general, the singers seemed to have little affection for living people. The greatest opprobrium was directed, of course, at Océane’s ex-boyfriend, a figure of such universal depravity that rappers could speak confidently about “paedophilia” and “incest” as well as rape: “Because of your ex, you went away too soon / He made you suffer incest, my hatred has no words.” But everyone else was implicated, too. The people who watched Océane’s broadcasts, for instance, were entirely morally corrupt. “Most of them are whores in fact, and that’s the truth,” opined one rapper, demonstrating that Océane’s story of male abuse had had no effect on the way he spoke about women. Women were despicable, just as men were; all were part of the universal corruption. “People have changed,” wrote one of these same rappers in another song, “I’m already scared of the future … If I’d known human hands were so dirty / I swear I’d have shared my life with an animal.” The human world was unendingly, incurably degenerate.

Which leads us to the point: Océane’s main merit for these rappers – and the reason why she could be spoken of in such hallowed terms – was that she was dead. They were not fascinated by the person she had been, nor were they motivated by a general protectiveness towards life. No: they were inspired by the fact that she had made the spectacular decision to leave behind an irredeemable world. In killing herself, she had realised a part of their own fantasy that they could never fulfil – and often they tried to “borrow” her suicide for themselves, to suggest that they had come very close to that act themselves, and so to include themselves in its glamour.

Were these just sad loners, expressing extreme but ultimately anomalous feelings? Possibly. But it is also the case that they were amateur rappers who copied their styles from more famous figures, and their moods, too, were unoriginal. They were not just expressing their own angst; they were parroting a world-despair and a death-fascination that lay at the heart of contemporary French rap. The world’s putrefaction, the unviability of life, the war of the end-times: these were the constant themes of rappers from the Paris suburbs, and in several cases the only poetic resolution was to leave it all behind. The most famous of all these rappers, La Fouine, had choreographed his end in a song called Quand je Partirai (“When I die”) – for how satisfying it was to imagine the world, contrite, at one’s graveside: “The day I die, certain bastards will offer their condolences / Where were they when the unpaid bills arrived?” Orelsan, meanwhile, a white rapper – and France’s richest – offered a straight-up suicide note: “Today will be the last day of my existence / The last day I close my eyes, my last silence. / For a long time I’ve looked for a solution to these irritations / Now it comes to me, and it’s so obvious.”

But if we zoom out from French rap, we realise that teenage culture is touched by the fantasy of exit at a much more universal level. As if to prove, in fact, that such thoughts were not merely their own, many of Océane’s obituarists mixed their verses with refrains from well-known pop songs, so endorsing their solitary gloom with the stamp of global celebrity. Some of them borrowed extracts from a hit by the French pop star Caroline Costa (someone else who had become famous from a TV talent show); the song is about someone who is no longer there – for an unstated reason – but once again its power comes from its expression, not of love or longing, but of the emptiness of existence.

Océane’s death was the first suicide to be broadcast live on today’s social media platforms. During the hours I spent watching her online videos, however, I never got the feeling that she was, in other respects, unusual. I saw traits in her common to a lot of people these days – and possibly to myself, even if they are most pronounced in the young: she was subdued, serious, intermittently funny, distracted by constant electronic tics, slightly unavailable to herself. In so many respects, Océane seemed entirely normal, and I sensed that her online exploit, too, would become more customary over time.

In the UK, the Samaritans can be contacted on 116 123. In the US, the National Suicide Prevention Lifeline is 1-800-273-8255. In Australia, the crisis support service Lifeline is on 13 11 14.

This is an extract from Rana Dasgupta’s Notes on a Suicide, published in Granta 140: State of Mind. Guardian readers can receive a 25% discount on an annual subscription to Granta. Visit granta.com/guard25 to take advantage of this offer.

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