“I’m nearly 24,” writes poor Judy Bishop, columnist heroine of the debut novel by former columnist Rose Heiney, who is nearly 24. “Any minute now my mid-twenties will fade into my late twenties, which will bloat gently along into my thirties, and before I know what’s happened I’ll have crawled my way into my forties, fifties, sixties and seventies, with nothing left but two years of eating mashed carrots in a home as a fitting preliminary to my sparsely attended DSS funeral. The clock is ticking.”

More a time bomb really, the kind that not only threatens to go off, but also keeps going off, with dreadful consequences for everyone close. Judy is a hot spot of self-hatred, disgusted by her body, her face, her aspirations, her lack of lovers, and planning with ever greater desperation how to dump her virginity in the Ipswich area. The bleak projection quoted above is Judy Bishop talking in her authentic voice, and using her private journal as confidante. It is not Judy B the columnist, who writes a weekly magazine piece about her brilliant metropolitan life with an almost criminal facility.

Judy B’s reports for public consumption are sparkling little frauds, with the tiresome signature of one convinced that readers share her obsession with her specialist subject – herself. This, for instance: “Oh, Dear Lord, it’s all Getting Complicated. Last week we established that my love-life has been growing somewhat hot in the Bedroom Department. You may, in fact, have assumed that there would be no column at all this week, as I would be firmly ensconced in the Chamber of Shag…” You can’t want more, please. It’s all lies.

This clever, dark brawl of a book can be read as a dialogue between the surface and the interior – that which is given out and that which is experienced, suffered. The two personae dance around each other as if they have a mutual need, and though they might appear to be tearing Judy apart, they might just be keeping her together as well. The most reassuring sign of her psychological balance is that she is more disgusted by her duplicity than she is proud of managing to carry it off.

The Days of Judy B can also be taken as the testimony of someone who might have fallen to pieces if she had not written it. The clues are everywhere. There is the author’s name. Her father is broadcaster Paul Heiney, which makes her mother BBC presenter and Times columnist Libby Purves. It also makes Rose the sister of Nick Heiney, who nearly two years ago, when he was about the age Rose is now, committed suicide at the family’s farm in Suffolk. The tragedy happened a matter of weeks after she started her novel. We are only up to page 43 when the private rather than the public Judy is herself musing about suicide. “To be honest, I don’t think it’s really for me. Suicide is for the disordered, the complex, the mercurial. It requires courage – grotesquely misapplied courage, but courage nonetheless… I don’t want to die, or actively to make the transition into death. I just want to slip away, which I suppose is what, in effect, I’ve already done, at the grand old age of 23.” There is an attempted suicide in the book, but handled with enough farce to suggest the author might be laughing the subject out of court.

The similarities between Judy and Rose keep coming – it’s the inconvenient truth at the shoulder of most first-time novelists who have followed the impulse to write about what they know. Both are passionate about musical theatre, above all Gypsy, above all with Ethel Merman. “I got absolutely obsessed by it [musical theatre],” says Rose. “It coincided with the one period of very real depression that I had. There is something about the raw energy of it just bounding out. I do think it is transcendent.”

Rose, too, has had, as they say, issues about the way she looks. She is tall, pretty and generously proportioned, which is not to say fat, as she has herself said in the past. It matters because she is also embarking on a parallel career as an actor, something she got into when she was studying at Oxford. She has a part in a forthcoming Miss Marple TV film and, when pressed, concedes that she would be “perfectly qualified” to play Judy B herself in the adaptation she is working on. “I used to be physically much bigger than I am now. Even after you have lost weight, you still feel some sense of otherness. I wasn’t comfortable in my own skin. I had to sit myself down and give myself a talking-to. Also, my new tactic is to become Offensively Naked Woman in the gym, walking about, not using the cubicles, realising that you look fine.”

As with her mother, it’s surprising when depression enters the picture. Contrary to some images of the condition, they both do so much – in Purves’s case, the tireless broadcasting, the journalism, the sailing, the books, the fiction. But then, particularly if you have read Purves on the subject of depression, you realise you are looking at the great antidote – work – rather than at the affliction.

Rose’s brother was beyond such remedy. “I remember the months just before his death as being so strange,” she says. “It was the summer of 2006, and it was very hot. I knew there was something terribly wrong. It was like being among animals before a thunderstorm. Suicide is something that you can’t consciously let yourself fear, because if you are worried about it, that means that you can try to prevent it, and that would have led to all sorts of guilt. But there was that sense of something really amiss, of the world not being the place it should be, a sort of… I sometimes try to remember things in colours; I think of then as a pitch-black, hot, burning time. The week after he died, I remember sunlight and breezes. I had been picking up on his suffering.”

She pays great tribute to her parents for the way they handled it all. “My mother sort of took me by the shoulders and said, ‘Now, you must not let this blight your life,’ and I thought, goodness, for her to have the generosity to say this at such a time…” They must have been shattered. “Yes, they were. But they are so brave, so professional. They just keep on working, which is something I’ve learnt to do. They did it so well. Soon after, I was in London and I thought, Nick has done this with such good grace, and left behind such a beautiful body of work.”

This is a reference to a collection of his writings that the family subsequently published as The Silence at the Song’s End. In among the juvenilia were some promising poems of great intensity and self-mistrust, including an apparently paranoid take on one of his sailing voyages. “As days wore on the crew began to feel resentment towards me/ For they did think that I, alone unhurt/ Was the sole cause of all the torment which they had to face.”

It’s impossible to know for sure why Nick took his life. Rose and her parents suggest that his state of mind, which had gone beyond acute, was made worse by a bad bout of labyrinthitis which he had suffered six years previously, and which may have left him with post-viral depression. What both Rose and her mother say – and very moving it is – is that Nick stayed for as long as he could.

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