The 29-year-old actress, who has been married to 47-year-old producer Nick Cokas since 2008, was spotted kissing the show's director, who has three young daughters with his actress wife Mary McCormack, in Hollywood last weekend.
A source close to the former 'American Idol' contestant told gossip website TMZ.com that she and Nick have been separated for 6 months and are living apart.
It is not yet known if Michael is still married or separated but according to EOnline.com he appeared to be wearing his wedding ring.
The new couple were later photographed enjoying lunch together at I Panini Di Ambra and holding hands as they made their way back to her car.
The musical series 'Smash' was recently canceled after just two seasons.
Sources previously told the New York Daily News that the brunette beauty planned to leave the show if it wasn't axed.
Two months before it was canceled in May, an insider said: "She refuses to do any interviews pertaining to 'Smash' now. She'll only talk about magazines she's in and her music. She knows it was a failure and she doesn't want her name linked to it, because nothing she has done has been a big hit. She wanted to break through and be a big star by the time she was 30."
It was also reported that she was rushing to get her album out and that Nick allegedly was holding things up.
A source said: "She refuses to work with any producers that can actually help her, and her husband, who is also her manager, isn't really any help."