OTTAWA - Justin Trudeau projects the image of a self-assured, impeccably turned-out, celebrity heart throb. But it wasn't always that way.

By the Liberal leader's own account, he was an awkward, insecure, pimply-faced youth who was traumatized by his parents' very public split and his mother's mental illness, an indifferent student who struggled in the shadow of his famous father to find his own metier.

That's the picture the 42-year-old Trudeau paints of his youthful self in a new memoir, which goes on sale Monday, with all proceeds to be donated to the Red Cross.

Although clearly timed to boost Liberal prospects exactly one year before the next scheduled federal election, Common Ground does not reveal any new specifics about the leader's still-sketchy plans for Canada.

It does, however, disclose in surprisingly frank detail some of the key life experiences — good and bad — that have shaped the man who would be prime minister and the values that guide him.

The first of three sons born to then-prime minister Pierre Trudeau and his wife, Margaret, Justin Trudeau has fond memories of both parents and of growing up in privileged circumstances at 24 Sussex Dr.

But he also recalls "a succession of painful emotional snapshots" that accompanied their breakup when he was only eight: escaping into Archie comic books when his parents were yelling at each other, his mother moving out of the prime ministerial residence, reading the lurid newspaper headlines about the separation and the wild antics of the newly free Margaret.

The notion that the dissolution of his parents' marriage was the result of "a flawed union between a cool and aloof man and an exuberant and uninhibited younger woman" is a "caricature," Trudeau writes. "It was that but also much more."

Among other things, he says his mother's lifelong struggle with bipolar disorder made life in the public eye "difficult, even intolerable" for her and was a big factor in the marriage's disintegration, although the stigma attached to mental illness meant it was rarely mentioned at the time.

"The truth is, my mother was very ill. Had her illness been of the physical kind, everybody — including her family and friends — would have been more sympathetic to her and understanding of her condition," Trudeau writes.

That stigmatization persists and, Trudeau argues, is deliberately stoked by his political opponents when they assert he's more his mother's son than his father's.

"They are appealing to those old misunderstandings and prejudices about mental illness."

Trudeau writes that the breakup left him with "a sense of diminished self-worth" because he hadn't been sufficient reason for his mother to stay.

He candidly recounts how his mother's health deteriorated after the split, to the point that "I began to feel that I had to take care of her, rather than the reverse." There was, for instance, the day Margaret urgently called him out of class to tearfully tell him that her boyfriend had left her.

"I did my best to console her, giving her hugs and patting her back and telling her it was all right, that things would get better," he recalls. "I was eleven years old."

When his father retired from politics in 1984, the family moved to Montreal where Trudeau was enrolled in College Jean-de-Brebeuf, the Jesuit-run classical school where his rigorously disciplined, intellectual, almost "monastic" father had excelled.

Some of the students cruelly tried to rub his nose in the latest gossip about his parents' split. He recounts one day when an older student handed him "a notorious picture of my mother that had appeared in an adult magazine" — presumably the one in which Margaret's knees-up pose exposes her lack of underwear.

Trudeau says he'd never seen the picture before and "obviously it set me reeling" but he knew if he betrayed any hint of hurt or shock "it would be open season on me for the rest of high school."

"I learned at Brebeuf not to give people the emotional response they are looking for when they attack personally. Needless to say, that skill has served me well over the years," writes Trudeau, who has made a virtue of his sunny approach to politics in the face of relentless Conservative attacks that he is "in over his head."

He also credits his wife, former Quebec TV host Sophie Gregoire, with keeping him on a resolutely positive political path. She is quick to tell him if she thinks he's "veering toward anything approaching a negative style" and has made it clear "she would not stand by and watch the petty feuds and frictions of political life poison my personality."

"Our marriage isn't perfect," he allows. "And we have had difficult ups and downs, yet Sophie remains my best friend, my partner, my love. We are honest with each other, even when it hurts."

While some women practically swoon in Trudeau's presence today, he writes that he was terrified of girls back in Grade 11, when Brebeuf went co-ed. He resorted to "nerdy showmanship" and wearing "bright green suspenders with jeans and pink flamingo ties" in a bid to stand out in the crowd.

But then he developed severe acne and "within a few short months, I went from being — or attempting to be — uninhibited to being morbidly self-conscious."

Trudeau admits he was an average student, applying himself only to courses that he liked, coasting through the rest, to his father's disappointment. When he "fairly deliberately" flunked a course needed to go from CEGEP straight into McGill law school, he realized he was subconsciously making a statement: that he was not like his father, the man who had been "my hero, my model, my guide, my instruction booklet to life."

"I had sabotaged that path (to law school), perhaps as a way of forcing myself, and my father, to come to grips with the fact that I would never be the academic high-achiever he was. That path was not mine."

Trudeau carved out his own path, going on to earn two university degrees, in literature and education. He moved to British Columbia, where he worked as a bouncer, a snowboard instructor and eventually a teacher.

Whereas his brother Alexandre (Sacha) emulated his dad and his youngest brother, Michel, rebelled and tried to live in anonymity, Trudeau says: "I occupied the middle ground.

"My Trudeau identity was a source of great pride to me but I also wanted to be judged on my own merits, as someone whose emotional temperament and intellectual attitudes stood apart from my father's."

For years, Trudeau kept a deliberate distance from politics. Having taken such pains to prove he was his own person, he says he didn't want to "negate those efforts by making the one career choice that would guarantee I would be measured according to my father's achievements."

But during the Liberal leadership convention in 2006, where he supported Gerard Kennedy, Trudeau discovered he loved and was good at the retail side of politics, the meeting, greeting, back-slapping and baby kissing — the very aspect of politics his father had always avoided as much as possible but at which his mother's father, the late B.C. politician James Sinclair, had excelled.

It was a revelation that eased his concerns about comparisons with his late father and ultimately prompted his plunge into the political arena: "I wasn't at all my father's son — I was Jimmy Sinclair's grandson."

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