10 of the Most Shocking Revelations From Christie Brinkley's Memoir: From Billy Joel's 'Other Woman' to Her 'Most Tortured Relationship' and More

Christie Brinkley offered an intimate look at the defining moments of her life in her new memoir, Uptown Girl.

In the book, released on April 29, the 71-year-old model reflected on the "fad diets" she had during her top model days. She included 1970s diary entries about her strict meals that read "like a registry of self- imposed starvation."

While she cannot believe it was her "idea of healthy," Brinkley admitted she was "so desperate to fit into designer clothes," which only had one size when she was a young model.

She added, "The thinner I was, the more likely I would be able to metamorphose into a dress or pantsuit — and the less embarrassed I would likely feel at work. Even so, I did a lot of modeling with the zippers open in the back and with photographers asking me to turn this way or that so the camera wouldn't reveal my jerry-rigged outfit."

According to Brinkley, Ford Models executive and former model Eileen Ford once gave her a "difficult instruction" to eat only fish as part of her diet.

Brinkley also took the opportunity to reflect on the 1994 helicopter crash in her new memoir.

The accident, which almost killed her and five others while they were heli-skiing in Telluride, Colo., was reportedly "sudden and traumatic, coming out of nowhere."

The National Lampoon's Vacation star added, "We had already taken two runs and were circling to land for a third, on the saddle of a faraway peak, when the helicopter just fell from the sky, plunging into a freefall from three hundred feet overhead, with no autorotation."

Brinkley was with her eldest daughter, Alexa Ray Joel, when the traumatic crash occurred.

"Suddenly, it became crystal clear that the only thing that really mattered in life and at death was the same: love. Love. I focused on Alexa Ray, holding her pure in my thoughts and hoping to project all my heart and soul to her so she would feel it at the very moment of impact," she continued.

In the book, Brinkley recalled how powerful the impact was that it ripped the cabin in two. Fortunately, no one in her group died.

After Christie's mother, Marge Brinkley, divorced her biological father, Herb Hudson, the matriarch went on to marry a man named Don Brinkley. Herb gave up his parental rights to the Vegas Vacation actress and her brother in a Los Angeles County courtroom afterward, before Don legally adopted the siblings.

"My heart skipped. Wait, Don wants me? This nice man actually wants to be my father? A bit of blood returned to my face, and I started to wonder what life would be like with Don as our dad. I suddenly felt a huge sense of relief, realizing that I would never be whipped, spanked, rubbed raw with towels or made to gag on soap again," she detailed.

In 1994, Christie and her third husband, Richard Taubman, tied the knot just months after their first meeting. They soon welcomed their son, Jack Paris Brinkley-Cook, on June 2, 1995, amid their troubled relationship.

As their marriage hit a rough patch, Richard reportedly betrayed the former The Masked Singer contestant when he told her he had tracked down her biological father and spoken with him by phone.

Upon learning Richard's betrayal, Christie was "so shocked and outraged" that she began to cry.

"We're going to make a deal. I'm going to walk away from you and the baby just like Herb Hudson did," she reportedly told Richard when they split days after she had given birth to Jack.

Christie added, "In that second, the room collapsed around me, as Ricky's words hung in the air like dark, dirty soot, choking me with so much shock and outrage that I felt breathless. Sometimes, history has a horrible way of repeating itself."

In Uptown Girl, Christie recalled meeting Billy Joel for the first time in St. Barts in 1983, saying, "He doesn't look very much like a rock star."

"The man was sunburned to a crisp, his face the same color as a cranberries and unctuous with oil, which he'd undoubtedly slathered on to soothe the burn, topped by what I like to call the 'Long Island Bubble': a carapace of curly, shellacked hair popular in the 1980s in parts of suburban New York."

Per Christie, she found Billy "charming and hilarious" during their first encounter at a dive bar. Although she knew she only wanted to be friends with him, their relationship eventually blossomed and led to their first date.

After Billy's divorce from his first wife, Elizabeth Weber, the "Piano Man" hitmaker began dating and living with Elle Macpherson in the early 1980s.

During an appearance on Watch What Happens Live, Elle said there was "some overlap" as Billy kicked her out of their apartment amid his romance with Christie.

"I think he was dating Christie at the time, just starting to," she shared. "So yeah, I got ousted, what can I say?"

In the book, Christie shared Billy insisted on calling Elle to "let her know" about their relationship — something the Jack and Jill star felt was "completely unnecessary."

"Still, that didn't stop rumors from circulating that she was waiting for Billy in his apartment the first time I ever went there, which wasn't true (the media seemed always to want to pit models against each other, even though there were more friendships in the industry than anything else)," Christie wrote.

According to Christie, Billy's song "Uptown Girl" is not about her.

"Unlike what many people think, Billy didn't write the hit about me — at least, not initially — nor about Elle MacPherson, but about someone who was as much fantasy as 'the Girl in the Red Ferrari,'" she disclosed.

But while they were in his home on Long Island, the "Turn the Lights Back On" singer reportedly told her he did not have to imagine the subject of the song anymore.

"You're right here in front of me, you're my real uptown girl," Christie quoted Billy in the memoir.

Before ending their marriage, Christie and Billy dealt with rumors about the 75-year-old singer-songwriter stepping out on their marriage.

"To this day, Billy continues to deny ever having had affairs, and I've always believed him," she admitted. "But on that New Year's Day in 1994, when he did finally straggle home, I asked him to leave."

Christie disclosed in Uptown Girl she "never wanted to end things" with Billy. However, his "other woman" became their marriage's last straw.

"I did everything for our marriage, constantly working to make myself, our home, and everything around us into whatever he could possibly want or hope for. I continually told him how much I loved him, making sure he always felt adored and appreciated, because he was," she said.

Christie continued, "But his drinking was bigger than the both of us — booze was the other woman, and it was beginning to seem that he preferred to be with 'her' rather than with me."

Christie moved on with Peter Cook, whom she was married to from 1996 to 2008, after going through three divorces. Unfortunately, their union became "the most tortured relationship" she has ever had.

In her memoir, the supermodel divulged she found out about Peter's affair with an 18-year-old assistant when she gave a graduation speech at a local high school in the Hamptons in 2006. At the time, a man approached her and told her, "That arrogant husband of yours has been having an affair with my teenage daughter."

"I was so stunned that I froze," Christie said, adding she looked into the audience where Peter was sitting with Jack. "As soon as I saw him, Peter's eyes were already trained on my face, as he began shaking his head, 'No.'"

She wrote, "When your whole world falls apart and you realize in a heartbeat you've suddenly become the cliche middle-aged woman whose husband is having an affair with a much (much) younger woman, what do you do?"