On the second day of her divorce trial against Peter Cook , Christie Brinkley broke down in tears as she recalled how her ex had an affair with his teenage assistant. "My world was completely shattered," she told the court, according to the New York Post . She said she learned the news after delivering a commencement address at a high school in NYC's Hamptons area in June 2006. She said the grads were taking turns collecting their diplomas on stage and Cook and son Jack cheering her on ...