This foreign born A list mostly movie actor who is actually a great actor and great looking is married. He and his wife have always had an open relationship but they are splitting because he has basically moved on to be with someone that he and his wife once had in a threesome. He wants to keep the fun and sex going and his wife says she is ready just for them to be a couple and not be always looking for a third or fourth. She was never really into it, but did it so he would stay.
Popular guess: Ewan McGregor