Until I spent time with Tracey Emin, I had never thought of art as an instant route to depression. Art as tragedy (Munch), art as horror (Goya), art as a window into Hell (Hieronymus Bosch), art that chronicles the descent into madness (Van Gogh), all of these cast light on some aspect of the human condition. But art that simply makes you want to string yourself up - that's different.

The Tracey Emin retrospective, which opened last week at the Scottish National Gallery of Modern Art, is not so much an exhibition, more a cry for help. By the time we have suffered the artist's experiences of rape, adolescent sex, abortion (several), drunkenness, “emotional suicide” and a seemingly never-ending list of failed relationships with exploiting men, we are left fairly close to death ourselves.

And since, for any normal, buttoned-up British male, the exposure to details of the female anatomy not customarily seen on a gallery wall is disconcerting, we have to add embarrassment as well. My only enjoyment came from studying the expressions of middle-aged men attempting not to flinch as they studied Emin's abortion series, or the confessions of her teenage diaries.

It's indecent, but is it art? Well, clearly it is, otherwise it would not be in the Gallery of Modern Art, Emin would not have been chosen to represent Britain at last year's Venice Biennale, would not have presided over the Royal Academy, would not have turned down a £1 million offer to recreate the tent containing the names of all the men she has ever slept with - destroyed in a warehouse fire - and would not, last Saturday, have been standing in her full décolletage in the centre of a ring of admiring acolytes, flaunting her wickedly crooked smile. She herself has no doubts about her talent. Her work, she announced at the weekend, is “seminal, fantastic and amazing”.

Time, clearly, for a little deconstruction. The best defence I have read of Emin's art was given last Saturday by this newspaper's chief art critic, Rachel Campbell-Johnston, who described her as an artist who holds up a mirror to our culture: “She is the sort of monster that our Big Brother world has made. She mixes all the ingredients - the cult of personality, the unabashed self-promotion, the blatant commerce - to make something that shows us with a mixture of repulsive brashness and unbearable poignancy how sad and superficial and self-serving it is.”

But the mirror is not held up to our culture at all. It is held up to Emin herself. Her art is egocentric to the point of obsession. So caught up in her life of self-absorption and self-destruction is she that anything of the outside world, in so far as it features at all, gets a mention only when it takes the form of the latest man to have used, abused and abandoned her.

There are some poignant glimpses of animals and birds, smudged and indistinct, but they are drowned out by the howls of adolescent rage and self-pity with which we are inflicted. Being with Emin and her art is like walking unexpectedly into the bedroom of a teenage daughter who is going through a bad patch. The room is a mess, the things she has scrawled on the walls don't bear looking at, and you can only hope that she will grow out of it.

That many of her cries of rage and despair are appliquéd on to quilts, or stitched with some skill on to tapestries, does not alter the fact that they are ultimately banal, unrelieved by irony, unleavened by poetry or anything that reaches out beyond the confines of her own, tortured world.

“My brains are all split up,” she wails. “I do not expect to be a mother, but I do expect to die.” “F*** school. Why go somewhere every day to be told you're late?” “Sometimes nothing makes sense and everything seems so far away.” “Some things I just can't live with and some things I can.” There are long accounts in her diaries of sexual encounters containing details one would much rather had been left out. Her diaries and the videos that she has made tell the kind of tear-stained stories one remembers encountering, after far too much has been drunk, at parties from which one should have escaped at least a couple of hours earlier. “Leave me alone,” she cries suddenly at one point.

Would that one could. Unfortunately Emin's case seems to be one of arrested development. What the mirror reveals is a woman caught up in the torment of a childhood and adolescence that she cannot grow out of - hence her demonstrable agony and our irresistible urge to head for the exit door. She is now 45, but seems for ever trapped in a peculiarly horrible early adult timewarp. “Look at me and my terrible life,” she demands. Sooner or later we are bound to answer: “Why?”

This, surely, is what undermines her claim to be an artist of “seminal”, “amazing” or “fantastic” status. For art, surely, has to show some way forward, some sense of its relevance, some connection with our world, our society or our collective consciousness. To be wrapped up so remorsely in oneself at the expense of everything else is to sacrifice any wider relevance - and the repetition of internal agony in the end is simply cloying; when the shock of the new gives way to the dull ache of the only-too-predictable, one has to wonder what else it has to contribute.

The late Mark Boxer used to tell a good story about one of London's most charismatic publishers, who was lamenting that, at the age of 50, he could not quite think what to do with the rest of his life. “Why don't you become a really good publisher?” said Boxer. Maybe Emin should decide that she has done enough complaining about her life and should concentrate instead on becoming a really good artist.

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