I’m not a poo joke kind of girl. No thank you. Yesterday I retched when someone described a smell. And yet the wild, warm effluviant humour of Broad City only made me like it more. This was a platonic love story about two women who adored each other. Rather than compete over boys or success, they supported each other unconditionally, and their very best days were spent yomping through the hot streets of New York complimenting each other’s bodies and/or choices. In the final episode, the two paused to stare out over the river, and Ilana told Abbi: “I’ve never felt so cool as when I’m with you.” Despite the fact that a filthy toilet they’d been dragging across town sat between them as they said goodbye, this was the first scene in 48 episodes that made me cry.

And it shouldn’t have taken me this long to realise it, but of course, of course, the gross moments were never just cheap jokes, never just plopped in for effect. It took five series to reveal to me the real role of poo jokes in this beautiful show but, yep, I realised that by opening the toilet door they offered two things. The first, an appreciation of women’s bodies as something other than sex-meat to be gazed at. In fact, as working machines, but ones that sometimes fart, and without shame. The second thing was a new authenticity, which reflected the grand honesty of the characters’ lives, and their insistence on being free. You saw it in their yomping, the way they danced down the street, and you saw it in the way they each had sex, both intimate and regrettable, but mostly in the way they’d decided to prioritise each other, their main relationship, despite all conventions advising otherwise. And not the kind of authenticity we often talk about today in relation to social media, with its careful absences and earnest crops, but a lifting, playful thing that leans into the vulnerability of youth. A way of being that is fearless and easy, if sometimes unhygienic.

The reason I’m grieving it still, I think, is tied to the fact that this was the end. Not of the show – I can cope with telly ending, if I wept at every series finale my cheeks would have track marks and my sofa would’ve left me – but of the friendship. It moved me with the reminder that friendships like these, formed in youth, founded in adventure and shared obsessions, spent in language littered with “dude”s, must end. They shape you and strengthen you, and then you grow up. Or, grow sideways, your focus shifting away from the pavement under your feet and off towards the horizon. Or grow inwards, further into your body.

Is it possible to have a best friendship like this in your 30s or 40s? One that exists still in that romantic strawberry light, intense in its intimacy, where it’s only her approval you seek and only her gaze that matters? Or is this ability to friend so hard it becomes a verb, something we lose, like puppy fat? I fear it is. In part, because we take it for granted – it’s rare to see friendship elevated and appreciated in the way it is on Broad City. With reverence. But also because of the usual dull reasons that most things fail – the admin of ageing, the layers of responsibility that we add like cardigans, one by one.

Time changes as it gets older, doesn’t it? Dries out like a leaf, becoming brittle and precious, rather than the languorous stretchy thing it was before, and inevitably some things get lost. When women are promised they can “have it all,” it means the luxury of both a career and a family – even in this utopia, friendship doesn’t figure. It’s seen primarily as a lubricant, a way to ease the journey towards having it all, rather than something valuable in itself. At the junction of adulthood, friendships are allowed to melt away, having served their purpose. They carried you there, an Uber to your real life, only to leave once they’ve seen you safely inside.

In Broad City, the two realised they needed to break free of each other in order to evolve, hence the end of the show. The beauty of friendship then is that people are still porous, can slip through each other and emerge richer. But the final scene pulled out to show a hundred other young women’s friendships blooming as they walked, devoted and sweet and cackling about money. Though it was the end of Ilana and Abbi’s friendship, their relationship was not really over because it was not unique. It was a portrait of true love in your 20s, before a necessary interval. Because, while the show has finished, I hear the friendships come back. When time changes again, flowing more easily to allow meandering conversations about the future and past, with new vulnerabilities, hard-earned strengths, and 50 new jokes about poo. And, fine, I’ll cross that bridge when I come to it.

Email Eva at e.wiseman@observer.co.uk or follow her on Twitter@EvaWiseman

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