Despite rumors of infidelity, Billy Joel is denying any claims that his separation from “Top Chef” host Katie Lee has anything to do with her questionable relationship with a hot, younger fashion designer.

Yesterday, the Piano Man, 60 announced that he and Lee had separated after five years of marriage, but his spokeswoman was quick to say their decision was “absolutely unrelated” to any claims of her being unfaithful.

According to a statement from both of their reps, “the decision [was] a result of much thoughtful consideration. Billy and Katie remain friends with admiration and respect for each other.”

But according to published reports, the marriage had been on the rocks for some time. And Lee, 27, has been rumored to be involved in a romance with Yigal Azrouel, a 36-year-old Israeli fashion designer.

The two have been photographed together and were reportedly spotted dirty-dancing together in Miami last January. Azrouel is even said to have referred to Lee as his “girlfriend.”

But a friend of the couple told the New York Daily News that it was simply “the age difference” that forced them apart.

“She is very career-oriented. She loves going out. She loves the city. When Billy isn't touring, he'd rather be on Long Island with his motorcycles and boats."

Joel’s ex-wife Christie Brinkley offered support for the legendary singer who has walked down the aisle 3 times.

Brinkley told Extra, “All I can say is he’s a wonderful father to Alexa. We’ve remained friends. We’ve been friends for many, many years, so obviously I’m very sad that this has happened and I wish them both happiness ... Alexa is doing great actually … She’s fine.”

Daughter Alexa, who served as the maid of honor at her father and Lee’s 2004 wedding, said she was the first to know of the separation, but that she also supported her father.

“If my dad’s happy, I’m happy and I respect any decision that he makes and I’m 100 percent behind him. So you know, I’m very protective of my father, so I want him to be happy…She [Christy] and my dad are really good friends. They’ve always been very, very supportive of each other throughout … trials and tribulations or any successes. They’ve always been there for each other, so I’m lucky to have such supportive parents.”

RELATED: Click here to read the full report from the New York Daily News.