Australian writer Helen Garner’s fiction has long been prized by people whose taste I trust. Yet when I’ve picked up her novels, I’ve bounced off them, like a spacecraft that has botched reentry into the Earth’s atmosphere. Every reader must have a writer or two like this, ones they sense they should like but do not. Garner’s work has seemed, in my brief encounters with it, thin and in want of polish.

Now comes “How to End a Story,” a barbell-weight book that collects three volumes of her diaries from 1978 to 1998, beginning in her mid-30s. At more than 800 pages, this is a lot of Garner (no relation). I almost put this one down, too, because it gets off to a tentative and makeshift start.

Book critics, like people who work in publishing, are always looking for an excuse to stop reading. But after a while I began to sync with her voice. By a quarter of the way in, I was utterly in her hands. Mea maxima culpa.

This is one for the introverts — the wary and the peevish, the uncertain of their looks, taste, talent and class status. Garner has an ideal voice to express late-night pangs of precariousness and distress, some more comic than others. Her prose is clear, honest and economical; take it or leave it, in the Australian manner.

She is, in her telling, the kind of person who gets mistaken for the staff at book festivals. People walk up to her out of the blue and ask, “What’s the matter?” (This is a special hatred of mine, too.) She fears for her table manners. Photographers say things to her like, “Your profile, it is not the best.”

If you have ever looked at a photograph of yourself and been floored by your own unsightliness, well, Garner is a laureate of this experience: “He showed me some photos he’d taken of me last year and I was shocked by my ugliness: spotted skin, lined face, ugly haircut, dark expressions. I mean I was shocked,” she writes. “I quailed at the possibility that I will be alone now for the rest of my life.”

Her sense of unworthiness extends to her own writing.

“I’m just a middle-level craftswoman,” she writes. And: “Grief is not too strong a word for what one feels before one’s own weakness and mediocrity.” She battles nuclear-grade levels of impostor syndrome.

Writers have kept diaries for myriad reasons. Anaïs Nin wished to taste life twice. Patricia Highsmith longed to clarify “items that might otherwise drift in my head.” Anne Frank wanted to go on living after her death. Sheila Heti felt that if she didn’t look at her life closely she was abandoning an important task.

These are Garner’s instincts, too. But she also says, charmingly: “Why do I write down this stuff? Partly for the pleasure of seeing the golden nib roll over the paper as it did when I was 10.” This writing served a more serious purpose. Garner told The Paris Review: “The diaries are how I turned myself into a writer — there’s my 10,000 hours.”The quotidian details of life shine in this book — her pot plants, shopping trips (“Kmart, fount of all goodness”), dinner parties, washing her knickers in a bucket, defleaing a dog, mending a skirt, going to the movies, keeping a copy of “Paradise Lost” in the outdoor bathroom. Sometimes she lives in small urban apartments, and at others in a rural house where she sees koalas and kangaroos and eagles and kookaburras.

Here is her report of one meal out: “At the hippies’ house for dinner, I find in my slice of quiche two foreign items: a dead match and a pubic hair. I hide them under a lettuce leaf and we go on talking.”

Her lit talk is ardent and adept: “Sentimentality keeps looking over its shoulder to see how you are taking it.” “Emotion,” though, doesn’t care “whether anyone’s looking or not.”

She appraises the blast zone around certain bores. About a dinner with academics, she writes: “Spare me from old men’s calm assumption that anything they say, no matter how dull, slow or perfunctory, deserves and will have an audience.”

This book does not need an injection of drama, but one arrives. After two failed marriages, Garner enters a relationship with a thorny, and married, male writer whom she calls “V.” (He is novelist Murray Bail.) They eventually marry, and his needs crowd out her own. She begins to feel like an intruder in her own apartment. He’s the one who gets to write there, while she must go elsewhere to work. He’s jealous of whatever success she has. Which is the host, and which is the parasite?

He commences an affair with another woman, a painter, and he prevaricates and lies. Garner pretends, for months, not to notice. She hangs on longer than you would think possible. It becomes harrowing. Their relationship is the mortar in which she is nearly ground into paste.

“For the first time,” she writes, “I begin to understand the women who stay with men who hit them.”

Work is her salvation and her bridge to the world. My plan is to return to her other books, and to wade in, this time, further than my ankles.