Christina Patterson: This tragedy has nothing to do with poetry, nothing to do with art

In his letters to the critic Keith Sagar, Ted Hughes described blissful fishing trips with his son, Nicholas, in Africa, Iceland and Alaska. Alaska, he said, was a "dreamland" where they "fished alongside bears" and "lay awake listening to wolves". It was a rare glimpse of the poet's relationship with his son, and of their shared passion for nature and silence. It is, therefore, beyond any kind of irony that it was in this "dreamland" that, a week ago, Nicholas Hughes hanged himself.

Hughes was 47. He was only one when his mother, Sylvia Plath, placed her head on a folded cloth in the oven, switched on the taps and waited to die. She had lined the door between the rooms to prevent the gas seeping in and harming her tiny children, Nicholas and Frieda, who was two. She had left milk for them to drink – milk and biscuits, as if milk and biscuits can replace a mother's milk, as if milk and biscuits can replace a mother's life.

But who can begin to imagine the frame of mind of a mother who loves her children, but can't get through another day? Who can begin to imagine the frame of mind of the man she loved and lost, the man who had to live with the loss, and the grief, and the guilt, and the accusations, and the hysteria, and, most of all, the daily sadness of two children who would never know their mother, but always live in her shadow? Who can imagine the frame of mind of the man who then watched another lover – the copywriter and aspiring poet Assia Wevill – kill herself, and their daughter, too? These things, luckily for most of us, are beyond our imagining.

There are enough myths surrounding the most famous literary couple of the 20th century – he Heathcliffian brooding intensity, she brilliant, brittle, fragile glamour, etc – and the world doesn't need any more. The world doesn't need, for example, talk of a Hughes-Plath curse, any more than it needs talk of a Richardson-Redgrave curse. What we know is the poetry: hers glittering, potent, and sometimes tender, his monumental, mythic and quiveringly alive to the natural world. Of the people, and their struggles, we can have only glimpses.

We know, for example, that Ted Hughes was a remarkable and brave man who bore the weight of his grief – and his reputation at the hands of the Plath acolytes as everything from murderer to devil incarnate – with a dignity marked by silence. It was only in letters, such as those to Sagar, and in his final collection, Birthday Letters, published just before he died, that he offered glimpses of the price he paid for that silence and of the depth of feeling beneath it. Hughes didn't live to see Birthday Letters win the Whitbread Prize, or to see it become that almost unprecedented phenomenon, a poetry bestseller. He didn't live to see that silence can stifle art, but he happened to believe that some things were more important than art.

We know that the children of that short, sad marriage struggled with the legacy of their mother's fame and death and did the best they could. Frieda, who has her mother's charm and her father's charisma, could easily have opted out of the limelight and the literary circus. Instead, she has refused, even though she knew it would mean constant failure by comparison, to deny the obvious artistic gifts her parents passed on. She's a painter, a poet (and a pretty good one) and a writer on poetry. Perhaps more importantly, she's someone who seems vibrantly engaged with life.

I met Nicholas only briefly, once. He was fiercely intelligent, charming and with his father's devastating good looks. His sister, who clearly adored him, once said he was "difficult". She knew, of course, about his struggles with depression. It was clear, from the way he talked about her, that he adored her too. How bad must it be to know that your sister has spent her life escaping from the shadow of death, and that you're about to rob her of her only close relative, too?

Suicide is a violent act that resounds across the generations. For those left behind, the wounds never heal. If you want poetry, you find it in poetry. You don't find it in death. This horrible, premature death of a brave, troubled man has nothing to do with poetry, nothing to do with art. Life, as Hughes knew, but Plath, tragically, didn't, matters more than art. Frieda knows this, too.