LATEST: Billie Joel‘s wife seen without wedding ring! Katie Lee and alleged pal Yigal Azrouel were spotted leaving the USA network’s party separately but a few minutes apart.  Katie, who wasn’t wearing her wedding ring, jumped into a waiting cab that Yigal was already in, a source revealed.

Billy Joel
‘s young wife has started a cozy relationship with a hunky male fashion designer, The ENQUIRER has learned exclusively.

The superstar musician – who turns 60 on May 9 – is being advised by close pals to dump gorgeous Katie Lee, 27, when his current concert tour ends in November, say sources.

For nearly a year, Katie Lee has been spotted out with Yigal Azrouel, a handsome 36-year-old Israeli-born designer.

"Billy is furious," a close source told The ENQUIRER. "His wife’s relationship with this guy is causing a split in his marriage.  "Initially, Billy thought it was great that she met a new friend, someone to occupy her time while he trudges through a long tour schedule. But now he’s become very concerned.

"Billy initially thought Yigal – being a male fashion designer – was gay. But when someone told him the guy was heterosexual and had women hanging all over him, Billy began to worry."

For the full story and to see exclusive photos of Katie Lee with Yigal pick up the latest ENQUIRER.