Olivia Wilde: Why My Marriage Ended

The first thing people notice about Olivia Wilde is that she's a knockout. The 27-year-old star of "House, M.D." is undeniably beautiful, but she insists that she has something else to offer as well: brains. "You can be a sexy, beautiful woman and be the smartest person in the room," the hottie tells Glamour in their June issue, where she also opens up about the recent breakup of her marriage and more.

In fact, the daughter of journalists Leslie and Andrew Cockburn talks candidly about her union with Italian prince/filmmaker Tao Ruspoli. It began when she was just 18 and they announced its end in February. "Everyone said it to me -- and I had to figure it out for myself -- but you change so much [over time]," Olivia admits.

Even so, admitting it was over was far from easy. "It was the hardest thing I've ever had to do.... We got engaged at Burning Man and married on a school bus. We were not conventional," she reveals. "I think the promise we always made was that if we are no longer happy, we won't continue. And it got to the point where I was working 10 months of the year outside of L.A. and he was doing incredible things in other places. We were no longer partners in crime."

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Still, Olivia says the decision to divorce doesn't mean her relationship was a failure. "The mark of a good marriage is partnership and continuing to feel inspired by your spouse. I had that with Tao. But the end is not necessarily the tragedy. Staying in a relationship that is no longer working is the tragedy. Living unhappily -- that's the tragedy."

Between her career and her current-single status, the brunette celeb has plenty of happiness on the horizon. She's got seven films coming out over the next two years, including this summer's action blockbuster "Cowboys & Aliens" and the comedy "Butter" with Jennifer Garner. Plus, there's always the possibility of a new guy. "I don't want to [end up in a new relationship], but I probably will. I wish I could play the field. But it's so not me. I go 100 percent into everything. And I'm a really good girlfriend."

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Read more about Olivia in the new issue of Glamour magazine, on newsstands May 10.

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