The Joey star, who is divorcing his wife, is romancing one of his costars

Matt LeBlanc, who filed for divorce from his wife last week, has a new real-life romantic costar: Andrea Anders, who plays his neighbor on the sitcom Joey, PEOPLE reports in its upcoming issue.

LeBlanc’s split from his wife of three years, Melissa, came as a surprise to the public – and to Melissa herself. The trouble started in January when LeBlanc, 38, unexpectedly announced that he was moving out of the Encino, Calif., home he shared with Melissa, 41, and their 2-year-old daughter Marina.

“It was very sudden,” Melissa’s longtime friend Kelly Phillips tells PEOPLE. “She was absolutely blindsided by what transpired.”

Then in March, Melissa accused her husband of being involved with another woman. LeBlanc, who had moved into an L.A. apartment near the studio where he tapes Joey, admitted he was.

Still, friends say, Melissa hoped for a reconciliation – and was stunned when, on March 30, an attorney for her husband called with the news that LeBlanc was about to file for divorce.

“She wanted to do counseling or therapy,” a pal tells PEOPLE. “But Matt just didn t want to work it out.”

After the divorce announcement was made, LeBlanc even brought the Wisconsin-born Anders – who recently shot a pilot for Friends producer David Crane – to the ranch house north of Los Angeles that he and Melissa had shared.

While LeBlanc’s rep declines to comment on the situation, saying, “We’re not interested in having a public discussion about private family matters,” others say LeBlanc’s involvement with Anders was one of the causes of the divorce filing.

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