Christie Brinkley testifies about husband's affair

CENTRAL ISLIP, N.Y. -- Christie Brinkley testified at her divorce trial Thursday that the day she learned her husband was having an affair with a teenager was the day "my life as I knew it had vanished."

The former Sports Illustrated model took the stand in state Supreme Court, a day after testimony by her architect husband, Peter Cook, and his former mistress.

Brian Platt, a police officer and the stepfather of the 18-year-old, informed Brinkley of the affair at a 2006 graduation at Southampton High School where the model was a speaker.

He tapped her on the shoulder, she tearfully recalled, and said, "That husband of yours won't knock it off. He's having an affair with my teenage daughter."

Brinkley said she looked at Cook, sitting in the front row, and when he shook his head in denial, she thought: "My God, it's true. He did do that."

"That was also the day that my world was completely shattered," said Brinkley.

Later, Brinkley's mood brightened slightly when her cross examiner tried to portray her testimony as acting.

"If you want to call me an actress, that's fine. I'm no Meryl Streep, but I have been in a very successful movie," she said with a sheepish smile while referring to "National Lampoon's Vacation."

"Thirty years later it's still got legs," she said.

During his testimony Wednesday, Cook said he had given his mistress, Diana Bianchi, a $300,000 payoff, had trysts in his office and Brinkley's Hamptons homes, and spent thousands of dollars on online porn.

Brinkley said she told Cook to give her his computer passwords "if you've got nothing to hide." She found e-mails there from Bianchi and the porn sites Cook visited.

"I know a lot of men look" at pornographic sites, she said. But, in Cook's case, she said he was trying "to connect with people" in their neighborhood.

"It was not a voyeur site. It was a meeting site," she said. "It was more than I could bear."

Cook had testified that he and Brinkley used pornography "to get the mood going."

Before learning of the affair, Brinkley said the biggest problem she perceived in their marriage was Cook's relationship with Alexa Ray Joel, her daughter with "Piano Man' Billy Joel.

Brinkley said Cook constantly picked on her 22-year-old daughter for the slightest things. "It was truly the area that pained me in our marriage," she said.

It distressed her, too, that Cook didn't want Alexa Joel to play the piano, especially since "I feel as though she's made my life a musical."

"You married me and my children," she said she would tell Cook. "You've got to find a way to love Alexa."

Joel testified that Cook treated her well before he married her mother, but was constantly on her case afterward.

Brinkley, 54, and Cook, 49, wed in 1996. She filed for divorce a decade later.