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Model-turned-actress Liberty Ross says she went through a "horrible" time following her ex-husband's affair with her "Snow White and the Huntsman" co-star Kristen Stewart but now says she is experiencing a "rebirth."

"It was horrible," she told December's Vanity Fair. "It was really the worst, really the worst."

"I have no words to describe what we went through," Ross said. "But I think, for me, something always has to completely die for there to be a rebirth. And, for me, I feel like I'm going through a rebirth."

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Ross' ex-husband, Rupert Sanders, the director of "Snow White and the Huntsman," came clean about the affair just 20 hours before photos showing Sanders and Stewart embracing appeared in Us Weekly and went viral. Both he and Stewart, who was dating longtime boyfriend Robert Pattinson, issued public apologies.

Ross' brother Atticus Ross, an Academy Award-winning composer, helped her through the media storm. He called Interscope Records' co-founder Jimmy Iovine, with whom Ross has recently been romantically linked in the press, who offered a public relations specialist. Another friend of her brother's let Ross and her two children stay at her home far from the paparazzi.

"I was able to be there completely secluded," Ross told Vanity Fair. "I just visualized [being] this sort of Masai warrior. I was just going to stand very still and very strong, and just let it all roll past me. I tried to keep as far away from it as I could and to understand that this is my family and it's the most precious thing to me."

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Ross recounted how she and Sanders began dating when she was 18 and her modeling career was taking off. Later, when she became pregnant with their first child, the couple moved to Los Angeles to focus on his career.

"I really felt like I wanted him to have his time to shine," Ross said, adding that she found herself increasingly isolated in L.A. "I went from really the high end of it all, and then I'm living on a hilltop in Hollywood Hills, breast-feeding."

The success of "Snow White and the Huntsman" seemed to make it all worth it. "I was so proud of him, what he'd done-what we'd done," said Ross, who has a minor role in the film, playing the mother of Stewart's Snow White. "We were a team, and the movie was made out of love."

After the cheating scandal broke, Sanders wanted to reconcile, but Ross said she knew the marriage was over.

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"I'm not a quitter," she told Vanity Fair. "I've done everything I could to be the perfect wife and mother and really support my husband. But I just didn't have any more to give, you know?"

Since then, Ross, who filed for divorce in January, has forgiven Sanders.

"We were together for 16 years, and that in itself is really beautiful," she said. "And we've created two exceptional lives together."