One of the most fascinating blips in the romantic history of leggy Oscar-winning actress Angelina Jolie was her brief marriage to actor Billy Bob Thornton, who holds himself accountable for their break-up. What does Thornton admit to doing wrong?

“I blew it because I didn’t think I was good enough for her,” Thornton told ABC's Nightline earlier this week. “She has one way she wanted to live her life and I had another way to live mine and I was just too insecure."

Thornton, 56, admitted that after meeting Jolie on the set of Pushing Tin and marrying her in 2000, his lack of self-confidence got the best of him. "I always thought I was sort of Quasimodo or the Phantom of the Opera. When I was with [Jolie] I think that really reached its heights," he said, adding that his insecure feelings were augmented by what he overheard. “I did feel like the Phantom of the Opera hiding in the catacombs,” he added. “People have actually said that I didn’t deserve to be with her.”

The couple parted ways in 2002 — one of many rough patches that Thornton talks about in his new book, The Billy Bob Tapes: A Cave Full of Ghosts. He also describes growing up in Arkansas and eating squirrel, struggling with ADD and dyslexia, and even developing an eating disorder while trying to control his weight for movie roles. “If you want to [lose weight] quickly, you just pick something and because I happen to know if you eat a can of tuna and a pack of Twizzlers, you will lose weight, I promise you,” he said.

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