Hurt but I shouldnt be

Had a fwb for about a month and just found out today for the past week he's been talking to his ex. He's going to drive 8 hours to go spend Christmas with her. And he's been ignoring me most of the week. Found out from a mutual friend. Now he keeps asking what's wrong and I just want to tell him to f off. Actually thought, stupidly, we could work into something more serious. He made such a big deal about having trust issues. And now he's the one lying. Go f-ing figure.