The cover-girl Christie Brinkley has scored spectacular revenge against her cheating husband by humiliating him in court. The spurned supermodel, 54, cried yesterday as she told her divorce trial on Long Island, New York, how she first learnt that her husband, Peter Cook, 49, was having an affair with a 19-year-old.

Brinkley, who appeared in the video for her former husband Billy Joel’s hit Uptown Girl, is now a fixture of society in the millionaires’ playground of the Hamptons. She told the court that she received the unwelcome news from the woman’s stepfather, a local police officer.

The stepfather whispered into her ear shortly after she delivered the graduation address at the Southampton High School, with her husband and son, Jack, cheering from the front row. “Suddenly, I heard these words . . . I heard, ‘That husband of yours just won’t knock it off. He’s having an affair with my teenage daughter and that bastard won’t knock it off and I have to come to you’,” she testified. “My world was completely shattered,” she said. “I asked him, ‘What did you say?’ But my eyes were fading out in like tunnel vision.

“I looked at Peter and I knew it was true and my knees were going to buckle and I saw little Jack’s face and I looked from Jack to the man and it felt like I was going to pass out.” Brinkley’s emotional testimony came a day after her estranged husband endured a humiliating six-hour questioning on the witness stand.

Cook, Brinkley’s fourth husband, was forced to admit under oath that he was a gold member of an internet swinger site who habitually spent $3,000 (£1,500) a month on online pornography. “I prefer young fit girls,” he wrote in his website profile.

Mr Cook, an architect, admitted that he had sex about a dozen times in his home and office with Diana Bianchi after hiring the policeman’s stepdaughter, then 18, with a view to having an affair. “He asked me how I would feel if he told me he was attracted to me,” Ms Bianchi told the court. “I was a bit taken aback, but I really wasn’t against it.” She said Mr Cook gave her $15,000 to buy a new car, hiding some of the money under a rock near his home. In the end, he paid her $300,000 “hush money” fearing that she might file a sex harassment suit.

Her stepfather, Brian Platt, said that Mr Cook was “very shaken up” when he told Ms Brinkley of the affair. “It appeared like he had urinated in his pants,” he said.

Times recommends

• Tewkesbury: when the memories flood back
• How I lost the gift of joy for a while
• The A-Z of winter style rules