"After six years of marriage, and having been separated for the past year, Katharine McPhee has filed for a dissolution of marriage from Nick Cokas," McPhee's rep told People in a statement. "The two have an amicable relationship and will remain friends. They ask that people respect their privacy during this time."
McPhee was still married to Cokas when she was photographed kissing Morris in Los Angeles last October. Reports stated at the time that she and Cokas were estranged.
Morris, however, was still married to actress Mary McCormack, though they are thought to have reconciled.
Photographers spotted McPhee and Cokas walking their dogs together back in March. Sources told Us Weekly that the two were "working on their marriage."
TMZ said Thursday that McPhee "just didn't want to be married anymore."