So you can spend a lot of energy trying to figure out if he's going to contact you again and when (believe me, I know!), or you can step back, accept that his absence makes you sad, and examine where that comes from. (Hint: it doesn't come from him and this specific action).
Learning how to handle tough situations like this is not a quick process. Knowing what to say when he calls is a short-term thing. You need to know (and really, not answering at all is probably your strongest choice at this time), but it's not the end-game. The end-game is having strong, healthy boundaries about the kind of treatment you deserve and respect that make handling situations like this easy.