Reese Witherspoon claims she isn't as sweet as you may think, and the 38-year-old actress definitely proved this with her most daring acting role to date in 'Wild,' a drama based on Cheryl Strayed's memoir 'Wild: From Lost to Found on the Pacific Crest Trail.'

Reese Witherspoon
Witherspoon claims she has never considered herself to be America's Sweetheart

Witherspoon, who is known for starring in rom-coms like 'Legally Blonde' and 'Sweet Home Alabama,' recently explained in the January issue of Glamour magazine why she isn't "America's Sweetheart."

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"I certainly didn't self-identify as anyone's sweetheart. I'm friendly, but I don't think I'm sweet. I'm honest," she told the mag.

The Oscar-winning actress also revealed that her personal life hasn't always been easy either. "I don't think I realized (in my twenties) that no one else makes you whole. You have to take responsibility for your own happiness. That took me until I was about 31 to know," she said.

Witherspoon was first married to her 'Cruel Intentions' co-star Ryan Philipe for seven years, and they share two children together, Ava, 15, and Deacon, 11. However, the pair officially divorced in October 2007.

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"It wasn't easy to realize," she continued. "Oh wait, I am purely responsible (for my life) - no relationship, no children, no nothing is going to make you a happy person. Every day you have to choose to find and cultivate your own happiness."

Reese Witherspoon
The talented actress also reveals that she is a very dedicated mother

Witherspoon has now been happily married to Jim Roth since March 2011, and they welcomed son Tennessee in 2012. "Well, I have to say a very healing part of my life is my wonderful husband, Jim. It's really wonderful being with somebody who supports me, who loves me, who is my No. 1 fan," she said. "That is such an incredible experience. You have to be ready for those things. I had to be in a place where I felt all those things about myself."

The 'This Means War' star revealed she is a very dedicated mother, and explained how her mind is always focused on her three children. "I don't think there's been an hour of my life since Ava was born that I don't think of my kids," she said. "I call it my CNN ticker tape: Is Ava OK? Yes. Is Deacon OK? Yes. Is Tennessee OK? Yes. Back to Ava."