A daytime lip-lock may have resulted in a major kiss-off. Page Six says actress Mary McCormack (from "In Plain Sight," "The West Wing" and Mrs. Howard Stern in "Private Parts") booted husband Michael Morris out of their Los Angeles home after photos surfaced this week of him puckering up and generally looking lovey-dovey with his former (and also married) "Smash" co-worker, Katharine McPhee.
"Mary threw Michael out of the house on Sunday night when he told her that TMZ had the photos and that they were about to be released," alleges a source.
McCormack, 44, whose new NBC show "Welcome to the Family" just got canceled, has three young daughters with Morris, 47: Lillian, 2, Rose, 6, and Margaret, 9.
"They've been together for more than 10 years and always had such a solid marriage," a source tells Life & Style. "He wants to keep the family together, but as far as Mary is concerned, it's over. There's no going back."
Not that Morris didn't try. Page Six claims he unsuccessfully attempted to buy the kissing pics to keep them from going public.
"Mary only found out this week about the affair after he confessed everything to her," maintains the L&S snitch. "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. But at the moment, Mary wants to split up with him."
McPhee, for her part, has apparently been separated from her husband, Nick Cokas, for several months. The onetime "American Idol" contestant, 29, married the 47-year-old producer in 2008.
"I never noticed anything with Kat and the director on set at the time," a "Smash" set insider tells People. "I do remember Kat's husband was always around and was very controlling."
According to Page Six, she was "blindsided" by the release of the photos.
"She is SO embarrassed she was caught," a spy tells Us. "She should have known better!"
As for McCormack and Morris, "Only time will tell if [they] can make things work and get over this," adds the L&S spy. "He loves Mary and is so sorry about what he's done."
And presumably sorry that he was captured doing it.
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