Brooke Shields Tells All in Emotional Memoir

Brooke Shields tells all about her celebrity romances, her mom and her crazy life as a child star. Subscribe now for instant access to our exclusive PEOPLE cover story and excerpt from her new book.

She's one of the most famous faces on the planet. Ever since Brooke Shields made her acting debut at 11 months old in an Ivory Soap commercial, she has lived her entire life in the spotlight – thanks to her mother, manager and constant companion Teri Shields.

"I was her greatest creation," says Shields, 49. "It was us against the world."

Now the star is opening up about her mom – and a whole lot more – for the first time in her upcoming book, There Was a Little Girl, exclusively excerpted in this week's PEOPLE cover story.

It was only after Teri's 2012 death from complications due to dementia that Shields could begin to consider writing about their tortured relationship.

"Even though I understood her better than anybody else," she admits, "I'm not sure I ever understood her fully."

Teri, a lifelong alcoholic who often left Brooke with a neighbor when she went out drinking at night, was outrageous and controversial from the start. It was Teri who often orchestrated her young daughter's "dates" with famous heartthrobs – and insisted she include a chapter on her virginity in her teenage memoir, making her, as Shields puts it, "the most celebrated virgin of our time."

Shields's book also details her famous crushes and relationships, from John F. Kennedy Jr. (they went out after he gave her a tour of Brown University) and Liam Neeson (he proposed to her without a ring) to George Michael.

Her crush on the singer, she says with a laugh, "was definitely one-sided." She was extremely close to Michael Jackson, whom she met when she was 13. "We loved each other," she says, but only platonically. "We just felt safe with each other." At Princeton, she fell in love with her classmate (and future TV Superman) Dean Cain and they were, she writes, "instantly crazy about each other." She lost her virginity to him when she was 22.

"He was incredibly and painfully patient with me regarding sex," she writes. "I made him wait and wait and my mom kept track."

In 1993, she met tennis star Andre Agassi through a mutual friend and they fell in love, bonding over the burden of childhood fame and overbearing parents. He helped her separate from Teri and rebuild her career, but their relationship soon developed cracks. After she made a guest appearance on Friends playing a crazed fan who flirts with Joey, Agassi got very angry. He "stormed off the set," she writes, and "drove all the way to Vegas," where he smashed all of his trophies in a jealous rage.

They eventually grew apart and divorced soon after Agassi confessed that he had been addicted to crystal meth during the early years of their relationship. Despite the drama, she credits him with helping her take the first steps toward independence.

But it wasn't until she became a mom herself (to daughters Rowan, 11, and Grier, 8, with husband Chris Henchy) that she finally wrenched free from Teri's hold. Sadly, just as she hoped to build a healthy relationship, she began to notice her mother slipping into dementia. It was a shock, she writes: "Her brain had so long remained seemingly sharp. I was sure it would be her liver that went."

Shields decided to write about her mother, she says, because she wants people "to see the fullness of her, the good and the bad." When she thinks of Teri now, she most remembers how they used to laugh together "till we couldn't breathe." And so, when it came time to find a place to put her mom's ashes, Brooke bought a beautiful silver urn and placed it on her marble-topped living room bar. This way, she writes, "she could remain forever close to the two most important things in her life: me and booze."

For much more of PEOPLE's exclusive excerpt from Brooke Shields's memoir and her revealing interview, pick up a copy of the newest issue, on newsstands Friday