However, O'Neal, 71, who was recently diagnosed with stage 2 prostate cancer, said his memoir about their lives isn't a tell-all. Both of Us, which arrived in stores Tuesday, was published to honor those 30 years.
"Well, I wrote it because I missed her, and it was a way to keep the line between us going," he said on Tuesday's Today show. "I still felt she was there when I wrote this."
O'Neal, who successfully battled leukemia, was supposed to appear on the NBC morning show Monday to discuss the book, but he left the studio in a whirlwind after having what seemed to be a panic attack. ("I don't know what was wrong," he told Matt Lauer. "I just broke out into a terrible sweat, so I just went home.")
In what turned into an emotional interview, O'Neal said he will start treatment for the cancer when he returns to California. But he didn't focus on his condition.
"I'm not over it yet," he said of Fawcett's death at 62 from cancer. "I got some relief writing the book."
Lauer questioned the fairness of the book, the details about fights and her addiction to antibiotics the original Charlie's Angels star isn't alive to dispute. He then questioned O'Neal's ability as a father, including his role in raising Redmond O'Neal, his 27-year-old son with Fawcett.
O'Neal didn't argue about being a bad parent, or even a bad partner ("I'm hard to live with," he said), but up until the interview ended, he stayed defensive about his relationship with Fawcett.
"She loved me," he said. "She said she loved me. I couldn't write a book if she hadn't."
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