While stating that Cook's behavior was "terribly destructive," Herman also pointed fingers at Brinkley, saying that "someone could raise questions about the mothers' four marriages and say she is not a good role model either."
Wearing a tan sweater over a powder-blue dress, Brinkley sat quietly in court. She took notes, dabbed her eyes with a tissue and then ran out of the courtroom to answer a call on her cell phone. Cook sat passively at the table with his lawyers, at one point showing them a message he'd received on his iPhone.
Herman shot down Cook's attorney's argument last week that Brinkley was blinkered with rage by saying, "It is completely understandable that she would be both appalled by her husband's behavior and concerned for the safety of the children."
When Cook's lawyer Norman Sheresky pressed the point of Brinkley's fury, the psychiatrist conceded that it was "not a great idea" for Brinkley to push to have the divorce case in open court, but he repeated his view that her anger was understandable.
In the end, Herman concluded in his report that everyone needed therapy, including Brinkley, finding it "important that she let go of this fear and. ... It is helpful for Christie to be in her own psychotherapy. She can learn how to accept that despite what has happened, the children love their father."
He added, "She needs an outlet for her anger and feeling of betrayal ... and work on deeper issues relating to her parenting and her choice of male figures with whom she gets involved."
The shrink also said his major concern with awarding Brinkley sole custody is that she "will see this as carte blanche for leaving Peter out of the lives of their children," and he strongly advised that the couple stick to a visitation schedule.
Saying that both Christie and Peter have done a "superb job of being parents" and that the kids feel "equally bound to both of them," he added that Brinkley is doing the children a "disservice, compounding the problem, by cutting them off" from their father.
The tell-all trial has been grueling for Brinkley, the infomercial queen and former wife of "Piano Man" Billy Joel. She broke down crying during her turn on the stand Monday while recounting how devastated she was when she found out about her husband's affair and love of porn.
Brinkley's lawyer, Robert S. Cohen, said the testimony was extremely emotional.
"Anyone who saw her testimony yesterday would be brought to tears," he said on "Good Morning America" today. "It was a very difficult day. She described going from a life that was virtually nirvana ... but Cook's relationship with Internet porn burst that bubble."
On Monday, Brinkley went from a sunny smile as she entered the Long Island courthouse to sobs while on the witness stand explaining the collapse of her marriage.
"I was devastated, and I was in this emotional tug of war where I was discovering more and more every day. ... It was a nightmare," Brinkley said through tears. "I had to deal with his Internet porn life. Anyone who would chase a teenager, a young girl, I mean, where is his judgment?"
She went on to recount how she attempted to explain the situation to the couple's two young children, whose custody could be determined by the hearing.
"I told them, 'I think Daddy has fallen out of love with me. When that happens, people move apart, but that doesn't mean Mommy and Daddy don't love you,'" Brinkley said.
Cook has been linked to three different women since separating with Brinkley, while the supermodel says that she has not gone on a single date.
"I haven't even thought about dating or anything like that. I've been completely focused getting the kids over this painful event," she said.