May 4, 2011 12:01 GMT  ·  By

Five years after her marriage to music producer Robert “Mutt” Lange came crumbling down amidst talk of his cheating with her best friend, country singer and now author Shania Twain is finally speaking out on the painful topic: “I thought I would never sing again,” she tells Oprah Winfrey.

Shania is now promoting her autobiography and, while she’s moved on with her life, and has even found love and happiness again with Nestle boss Frederic Nicolas Thiebaud, she says the pain of the divorce was still too much to take.

As the video below will also confirm (even though it’s just a snippet of the very lengthy interview), speaking of the divorce from Robert is no easy topic for Shania, even with her current husband Frederic in the audience to support her.

Fans must already know that Shania and Robert got divorced after word got out that he was having an affair with her best friend Marie-Ann who, at the time, was married to Frederic Thiebaud.

“Our lives were intertwined in every respect and I really was completely shocked,” the singer says of the divorce.

Desperate to make her marriage work again, Shania admits she even wrote a letter to Marie-Ann, who kept refusing to confirm or deny the affair, asking her to seek love someplace else, with another man and without ruining the lives of two families.

“By not understanding and not knowing the details your imagination is left to run wild. I never got the details. I phoned Marie-Anne and did everything I could to get the details out of her and she changed her number and that was it,” Shania tells Oprah.

As for moving on from the divorce, once she got confirmation (one way or another) that her husband had been unfaithful to her, that was the hardest thing ever, both personally and professionally.

“I figured mentally that I would never sing again. I hadn’t written a song without this man in 14 years... How do I even get started?” the singer explained.