The Oscar winner also shared how she relaxes, and it's a little TMI.
Reese Witherspoon has learned a lot in the 10 years since winning an Oscar for Walk the Line.
The actress, who will turn 40 on March 22, tells with Harper's Bazaar that she's never been more confident or optimistic for the future. "I'm much more open now. In my 20s, I was scared of everything. I didn't know what my career was," she admitted. "I didn't know why people liked my movies. I was wary of interacting with people."
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Witherspoon -- who was married to Ryan Phillippe from 1999 to 2007 -- says she even had uncertainties about her career at that time. "I was 25 when Legally Blonde came out, 26 for Sweet Home Alabama, and 29 for Walk the Line," she recalled. "And I was scared, really scared."
The mother-of-three doesn't feel that way anymore. "Now I feel like a different person. It's a great thing getting older," Witherspoon said. "You are who you are; you say what you mean."
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The Wild actress has also found a way to decompress from the pressures of Hollywood. "You know what I like to do? Reorganize bookshelves and my sock drawer," she shared. "[My husband] Jim [Toth]'s like, 'What have you been doing for four hours in your closet?' I'm like,'Um, reorganizing my underwear?'"
While Witherspoon may have had some self-esteem issues in her 20s, she was certainly holding her own when ET caught up with her at the Glamour Women of the Year Awards in November -- and she gave much of the credit to her husband. "I could never start a company, I couldn't climb a mountain, I couldn't have three kids if I didn't have a supportive husband," she bragged. "He's my biggest champion and my biggest fan."
Here's more of Witherspoon's interview with ET: