For a long time I have worried about where I will be when I hear the announcement of Joni Mitchell’s death. I don’t want it to be when I am in transit, or about to do a literary festival or attend a family celebration. I need to be on my own. I need to close down the internet, draw the curtains and spend the next two days repeatedly listening to the albums Hejira, The Hissing of Summer Lawns, Court and Spark, and Blue. I am going to be traumatised. This won’t be just a death; it is going to feel like an emotional amputation. No other artist has meant as much to me, or has taught me so much about myself. This week the news broke that Mitchell, now 71, had been found unconscious and was in intensive care. A childhood survivor of polio, her health has not been good for a long time. She has, by her own admission, wrecked her voice through smoking and is suffering from a mysterious skin condition called Morgellons disease. She is not in great shape, and I worry that our long ride together may soon come to an end.

You start out being a fan of some teenybop star when you are 12 or 13 and then grow out of it. You cringe and shudder when you remember those hot, passionate feelings for the little doe-eyed boy-man, deny that you ever had a Smash Hits centrefold of Donny Osmond or One Direction on your bedroom wall. But what if you started to listen to someone when you were 17, someone who was one of the greatest of their generation and of the century, who articulated that particular moment when opposing longings for love and for artistic self-expression are waging war in you? And nearly 50 years later, you are still a fan, and the person whose music means everything to you is hospitalised and in danger and you’re holding your breath; you’re ready to be heartbroken.

Mitchell is one of the greats – as great as Bob Dylan, maybe greater, but it’s not a contest; she just means more to me than he does. If she means nothing to you, too bad, your loss. Just don’t persecute her. One element of my devotion is anger at the raw and rawer deal she has received from the music press, since the contemptuous awarding of the title “Old lady of the year” by Rolling Stone, as if she were more of a groupie than a great lyricist. Mention Joni Mitchell today and you may still be greeted by a sarcastic falsetto imitation of her song Woodstock, from the early years before the cigs introduced gravel into her voice. She was at her height in the early 70s, a decade of bad clothes and celebrity sex pests, of overblown prog-rock and a general political malaise. Punk came along and kicked in anything with nuance, sophistication, feeling, lyricism. She was shunted into the same derisory cul de sac as, say, Peter, Paul and Mary or Donovan – hippy and drippy – when she was a jazz singer, a consummate composer, a poet and a thinker.

What she always lacked, to oppose all that dismissive contempt, was the obsessiveness of the male fanbase: the Deadheads and Dylanologists who catalogue and compete for record-collection kudos among a fraternity of admirers. Where are the dry, 1,000-page volumes of musical Joni-trivia, the conferences, the PhD dissertations? We just locked the door and listened on our own. On hearing the news of her hospitalisation, the crime writer Val McDermid tweeted: “Distraught to hear Joni Mitchell in intensive care. Her music inhabits my heart, my very soul.”

I accept that Mitchell has not been the easiest star to love. She gives little back to her fans and her views on feminism have been disheartening to say the least. She seems to have lately rejected everything her generation stood for, from its ideals to its clothes. There is a tendency to think that if you could only meet the person of whom you are a fan, you would inevitably become friends. For a long time I imagined that I would be hitchhiking one day and Joni would pick me up and we’d drive along under a limitless sky talking about the men we had loved and the trap of marriage and the perhaps unavoidable tendency of romantics to become cynics, and the desire for Paris gowns and lacy dresses and skating on a frozen lake in a snow storm … and I wouldn’t need to tell Joni a thing about me. She already knew. She’d written my emotional biography. “I am a woman of heart and mind / With time on her hands / No child to raise”. “Sharon, I left my man / At a North Dakota Junction / And I came out to the Big Apple here / To face the dream’s malfunction.” And, definitively, “Nothing is capsulised in me / On either side of town / The streets were never really mine / Not mine these glamour gowns.” If I could express any of that in a novel, so succinctly, I would have done. But she’s the genius, not me.

I hate the media and the music business for their disgraceful treatment of an artist of her stature. And I have to concede, when I read interviews with her, that these blows have not been borne graciously. They have not been borne at all. She seems lonely, angry, bitter, paranoid and afraid. I worry about her. Had she been a man, she would be on her third or fourth considerably younger partner, with a new young family, that complacent second act that women are denied. Maybe if she’d been a Buddhist or got into some faith system, been born again into a cult or the church, she’d have found peace. But in a recent interview in the Sunday Times, she laid into hippies, all contemporary music, Bob Dylan, and again, feminists. She nixed a biopic starring Taylor Swift because all the young star could offer was cheekbones. Her reunion with the daughter she had given up for adoption went sour. Her tone is autocratic, arrogant and angry. She reminds me, in a way, of Philip Roth, another raging titan of the American arts.

She has called herself “a scientist of love”; how to love is what she’s trying to get to the bottom of. Like Jean Rhys, she has drawn the anatomy of a woman’s heart, the men we fall for, the loneliness, the fatal choices. The accretion of age, the disappointments of living, are part of the journey we’ve all been on with her, so this life-long fandom can’t have a happy ending. Or even a happy middle. Pity the poor children with an indelible online record of the day they wept when they heard Zayn Malik was leaving One Direction. Perhaps the lifelong experience of being a fan, an admirer, an acolyte or a student of an artist will turn out to have been a fluke, a small window of privilege, and from now on careers will burn up in a year or two, the experience fleeting for the adorer and the adored alike. I don’t think she knows how much she’s venerated. Or maybe she knows and it doesn’t matter. It fulfils nothing. It makes no difference. She’s as alone with her music as we are.