After eight years of silence, Meg Ryan is finally opening up about her failed marriage to Dennis Quaid and the reason for their shocking split.

In 2000, Ryan, now 46, famously had a fling with her Proof of Life co-star Russell Crowe; the affair ended her marriage to Quaid (with whom she has a son, Jack, 16).

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But she tells the new issue of InStyle (excerpted by Entertainment Tonight), "Dennis was not faithful to me for a very long time, and that was very painful.

"I found out more about that after I was divorced," she adds.

Of Crowe, she says: “I think he took a big hit. But Russell didn’t break up the marriage. He was definitely there at the end, but it wasn’t his fault. I was a mess. I hurt him too at the end. I couldn’t be in another long relationship, it wasn’t the time for that. So I got out.”

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She continues, "My time as a scarlet woman was really interesting. As painful as it was, it was also incredible liberating. Now I was utterly free. I didn’t have to care about what people thought."

She also says being dubbed "America's Sweetheart" was stifling at the time.

"It's an old-fashioned idea, so anachronistic. I understood it was a compliment about being lovable, and it felt nice ... but it also felt, after a time, like ideas were being projected onto me that had nothing to do with me," she says.

"The girl next door to what?" she continues. "I never felt like a very conventional person."

So she says she purposely chose to take a break from the public spotlight.

"I've been famous for a long time, and these last years, there's been a great lull," she says. "So it has been me throwing a backpack on, traveling a lot -- it's been fantastic."

She found something special along the way: Daughter Daisy, a baby girl from China, whom she adopted three years ago.

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"I don't feel like I adopted a child. I feel like I just got this unbelievable companion," Ryan tells the magazine. "Daisy is brilliant. This kid says things every day that make you just stop and stare at her."

http://www.usmagazine.com/news/mega-ryan-dennis-quaid-not-faithful-to-me...