MOST celebrity biographies are airbrushed affairs, designed to show the subject in the best possible light.

Imperfections in a person's life are glossed over or minimised. Not so with Lily Allen’s autobiography, My Thoughts Exactly. Its remarkable honesty about herself and others makes it stand out from other tomes of the same genre. As she says in the opening lines, "this isn't a normal memoir".

Allen shines a light on the imperfections of her life, starting with her dysfunctional childhood. Her parents were a showbiz couple: comedian and actor Keith Allen and film producer Alison Owen were often absent or non-attentive, focusing on their careers rather than their children.

While Keith was living it up with his buddies at London's famous Groucho Club, Lily and her sibling were left alone in one of the rooms. "I knew the phone number off by heart by the time I was six," writes the singer at one point, a sentence that would be amusing if it were not so tragic.

Sent to a private boarding school at a young age, Lily longed to be taken care of, but rarely was. She grew up to be talented but deeply scarred: addictions relating to sex, drugs and alcohol are referred to throughout the book, as is her tendency to be codependent, always relying on others for emotional and practical needs.

The book lists agents, lawyers, assistants, stylists: a small army of people to make Allen's life tick. Chaos is never far away: she attends nine different schools, sells Ecstasy while on holiday in Ibiza, aged 17. She takes an overdose as a cry for help. She collects thousands of pounds worth of parking fine but hides them, pretending they don't exist.

She cheats on her husband, hires a female hooker, and the marriage goes sour. Other tragedies, which were not her fault, occur: her first child is still born in traumatic circumstances, an assault by an unnamed music business representative is appalling, and she narrowly escapes a nasty end when a deranged stalker breaks into her home.

It's vivid, powerful, shocking stuff. The breezy girl who first charted with Smile in 2006 is very long way from these pages. At times, Allen’s self obsession gets a bit much - there are hardly any references to cultural or political events outside the bubble of her showbiz life.

What make this a great read, however, is her tremendous authenticity about her own failings. I finished the book admiring her strength: she's endured more than many people go through in a lifetime. The book pulls no punches in telling her (sometimes ghastly) story with coruscating honesty, and the people around her don't always come out of it well.

Allen uses the book to talk about women's travails in a world where men often let them down (although Coldplay singer Chris Martin comes out of it as a minor hero). I hope she rockets upwards from here. Goodness knows, she's got it in her.

Lily Allen's My Thoughts Exactly is published by Blink Publishing