"There was a time when I just came back that I couldn't even concentrate on playing because there was a lot going on in my mind, a lack of self-confidence," Capriati told Reuters in a telephone interview.
"Forget about tennis, I was scared to open my mouth. I didn't even feel worthy of saying something and not sounding stupid.
"I was an emotional basket case," said Capriati, who spent more than two years away from tennis after a demoralising first-round defeat in the 1993 U.S. Open and was detained by police for shoplifting and drug possession.
"Now a lot has changed and I can separate a lot of things. And if I can't, I make the decision not to even try to play tennis."
Tournament promoters are counting on Capriati's popularity to sell tickets this week as she and Chanda Rubin are the only Americans in the eight-woman field at Los Angeles' Staples Center.
Southern Californian natives Serena and Venus Williams and Lindsay Davenport have pulled out with injuries, leaving Capriati as the big attraction.
She begins the round-robin phase of the event against Japan's Ai Sugiyama.
NEGATIVE PUBLICITY
Three-times Grand Slam winner Capriati still dislikes making public appearances but is always willing to take a stand on issues she believes in.
In 2002, Capriati got into a public spat with the United States Fed Cup coach Billie Jean King about whether private coaches should be allowed at team practices. She stuck to her point of view despite the negative publicity that ensued.
"I trust myself more," Capriati said. "It's also because of the feedback I got. People want to hear what I have to say and respect what I say. But mainly it comes from myself."
While the fifth-ranked Capriati does not start as the favourite this week, she is regarded as one of the few players to have a serious chance of beating defending champion Kim Clijsters or French and U.S. Open champion Justine Henin-Hardenne.
Last year in Los Angeles, Capriati lost a three-set heartbreaker
Six weeks ago, Capriati suffered another bad defeat, when she fell to Henin-Hardenne in the semi-finals of the U.S. Open, surrendering big leads in both the second and third sets. After the match, she admitted to choking and called it the worse defeat of her career.
After that match, Capriati said, she went from being angry to feeling drained. Now the former world number one knows she must turn herself around mentally if she is to have a chance of reaching the top again.
"I came as close as you come to winning," she said of the semi-final. "It wasn't my tennis that made me lose, it was a lot of different things going on, high drama, high emotion.
"It was also because the Williamses weren't there and (people were saying) I should win. But there were other good players there. For whatever reason, I didn't (win) and I can't look at it like it was my only chance. That's not very positive."
NUMBER ONE
When Capriati returned to the tour full time in 1999 after battling burnout and the fallout from her arrests, few analysts believed she would ever get into the top five again.
Capriati is delighted to have proved them wrong by winning two Australian Open titles and the French Open, as well as making the world number one spot for several spells in 2001 and 2002.
"Coming back after the layoff, I wasn't really sure what to expect," she said. "Maybe there were times I counted myself out. I'm just happy to be playing and to have the results I've had. If nothing ever happened from here on, I still feel I've had a noteworthy career."
While Capriati's peers such as Monica Seles and Davenport are out of action with injuries and could soon retire, Capriati sees herself playing into her 30s.
She recently read the autobiography of five-times Tour of France winner Lance Armstrong and said she was inspired by how he approached the struggle of getting to the top and staying there.
Capriati has won nearly $7 million in prize money but says she has no plans to relax for the rest of her career.
"Tennis is what I do and is part of who I am," she said. "It doesn't mean I'm going to be nonchalant from here on out. I'm happy with what I've done but it's a challenge to try to win more."