Billy Bob Thornton says his marriage to Angelina Jolie [photos] crumbled because of his insecurity.
"I didn't think I was good enough for her," Thornton, who was married to the actress from 2000 to 2003 tells 'Nightline'.
"She has one way she wanted to live her life and I had another way to live mine and I was just too insecure."
"When you're in a relationship, any two celebrities or whatever, you know, I think that puts on a lot of pressure."
"When Angie and I got married, during that time, I was more famous than she was to start with and then she becomes this big thing, it's hard in these relationships."
"I felt like the Phantom of the Opera hiding in the catacombs," he says. "People actually said that I didn't deserve to be with her."
Thornton says he and the Jolie remain "good friends" despite their failed marriage.
"We had a great time together," he explains. "We had a great marriage and I chickened out because I didn't feel good enough. That's all that happened. It was no big deal, we never hated each other."