"It was horrible," she said. "It was really the worst, really the worst."
The British model turned actress found out about her director husband and the Twilight actress' affair 20 hours before intimate photos of them were published.
"I have no words to describe what we went through," the mum-of-two said in an interview with Vanity Fair.
"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."
Liberty had the support of her brother Atticus during the difficult period. The Oscar-winning composer of The Social Network reflected on the media storm caused by Rupert's infidelity.
"To some extent at that moment, Rupert was in denial, and Liberty didn't know what was going to happen," he said.
"I'm texting people because I know this is going to be huge. I knew this had all the makings of what our world has become. This is going to be f***ing big, and Liberty needs to be protected.
"It was about it not destroying [Liberty]. I don't think people understand what being in the eye of that storm is like."
A friend of Atticus's, Jimmy Iovine [to whom Liberty was later romantically linked], offered Liberty and her two children Skyla and Tennyson his house as a haven from the media attention.
"I was able to be there completely secluded," the 35-year-old said. "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." Despite Rupert's public apology and statement that expressed his desire to reconcile Liberty realised their marriage was over.
"I'm not a quitter," she says. "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?"
Despite the public breakdown of their marriage Liberty says she forgives her Snow White And The Huntsman director husband.
"We were together for 16 years, and that in itself is really beautiful," she said. "And we've created two exceptional lives together."
Liberty filed for divorce from Rupert in January.