Katharine McPhee may have split from her husband before she started hooking up with director Michael Morris — but Michael certainly didn't end things with his wife!

Life & Style can reveal that his wife, actress Mary McCormack, 44, was shocked to find out he's been carrying on a relationship with Katharine, whom he directed in the series Smash, and now she wants to end their relationship.

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"They've been together for more than 10 years and always had such a solid marriage," an insider tells Life & Style. "They have three daughters, so it's incredibly sad. He wants to keep the family together, but as far as Mary is concerned, it's over. There's no going back."

Michael, it seems, hadn't split from Mary when he began his alleged fling with the American Idol alum.

"Mary only found out this week about the affair after he confessed everything to her," the source explains. "She had no idea anything had been going on. The last thing she ever thought was that he was seeing another woman."

The duo, who wed in July 2003, have three daughters: Margaret, 9, Rose, 6, and Lillian, 2.

EXCLUSIVE: Katharine McPhee and Husband Split Months Ago

“She is beyond furious and is absolutely devastated. So is Michael. He really wants to make it work between them and try and save the marriage," adds the insider. "But at the moment, Mary wants to split up with him."

As Life & Style reported yesterday, Katharine, 29, ended her relationship with Nick Cokas, her husband of five years, in March — months before she started seeing Michael. Katharine and Michael were recently photographed kissing in Hollywood.
 
"Only time will tell if Michael and Mary can make things work and get over this," the source tells Life & Style. "He loves Mary and is so sorry about what he's done."