07/11/2011 02:53 pm ET Updated Sep 10, 2011

Katie Lee: Billy Joel's Ex-Wife Talks Divorce, Surfing, 'Groundswell' (VIDEO)

In 2009, 29-year-old celebrity chef Katie Lee split up with her husband of nearly 5 years, rock star Billy Joel.

Last month, Lee published "Groundswell," a novel about a woman who divorces her celebrity husband.

You could draw certain parallels between Lee's real life and her fictional debut. But if you did, you'd be mistaken--or mostly mistaken, at least, says Lee.

"Like any writer, I did take inspiration from my own life," Lee told Huffington Post Divorce during a recent interview in Los Angeles. But, she insists: "it is fiction."

Still, it's hard to overlook the glamorous details pulled from Lee's life--the MET's Costume Institute Gala, for instance, which Lee attended and which furnishes the backdrop for the book's opening scene--and the fact that her protagonist, Emma Guthrie, retreats from the spotlight and regains her strength by learning to surf, a detail that closely parallels her own recovery from her split with Joel. "Surfing for me was a way to take my mind off everything else," said Lee. "I was scared, but it got me out of my own head and also conquering that fear really gave me a lot of confidence to feel like I could be on my own."

While the question of what's truthful and what's fictional in the novel may be somewhat ambiguous, there's one thing Lee isn't ambiguous about: her friendship with Joel post-split. Lee says she and her ex are "lucky" to be among the "really small percentage of divorces" where the couple remain friends. "Not many people can say that," says Lee. "We had a really good relationship when we were married. We just weren't meant to be married."