Presumably somewhere in Los Angeles
Cheated on Donna Logan 
Mark Mallory was the unemployed, possessive boyfriend of Donna Logan, who pressured Donna into moving in with him, then discouraged her from spending time with her family. Mark became jealous when Donna started working with Rocco Carner at Griffey's Diner, angered to find that Rocco had lent Donna her rent money. Mark objected to Donna's ambition to become a model, but grew closer to her when he opened up about his unhappy childhood. However, because Donna thought she might be pregnant, Mark went to bed with another woman, and Donna caught them together. Mark left the canvas after Donna dumped him and hasn't been mentioned since.