Tom is at a party, hanging at the bar. A guy he knows, Matt, comes up to him to say hi. They talk, then -
Matt: Well, it's good to see you again. Enjoy the party.
Tom: Thank you.
Matt moves off/heads off/leaves.
Matt doesn't leave the party just Tom. Which of "moves off", "heads off" and "leaves" should I use? Or maybe all of them would be okay?