She told the court Monday that after finding out her husband had had an affair with the 18-year-old woman, the model put on a brave face and threw a birthday party with 30 kids.
"That's the most important thing--to have a big, happy family," she said.
The court heard testimony last week from Cook, 49, and his former mistress, Diana Bianchi. Cook said he gave Bianchi a $300,000 payoff, had trysts with her in his office and Brinkley's Hamptons homes and spent thousands of dollars on online pornography.
Brinkley said Monday she tried to spare her two young children the messy details of the breakup, including her discovery of Cook's Internet porn habits. She told the children: "I think Daddy has fallen out of love with me," while assuring them they would always be loved.
As the scandal became public, she took the children on a private plane for a vacation in Colorado.
"I took them to the top of a mountain, and we camped out under the stars," without TV or Internet access, she said.
While they were away, she said, "Ms. Bianchi spilled the beans. She went on TV to get her 15 minutes of fame."
Under questioning from her lawyer, Brinkley said she had remained faithful to Cook. And, though she's divorcing, she's not interested in dating.
"I think the kids have been through a lot of changes," she said. "I just don't think this is the time for that."
