My ex wants to get back together, but i dont, but i dont want to keep hurting him?

Well first off if you are "practically over him" and you go back out with him you are just going to be hurting him anyway. It sounds to me like you don't love him, not saying that to be mean it just sounds like you fell out of love with him. If he was mean and degrading to you near the end of the relationship then it sounds like a relationship that doesn't need to be picked back up anyway. It sounds like the two of you are both better off with out each other. Let him move on and you do the same...and as for the guy who is moving to Canada, Long distance relationships very rarely work out, although it is altogether possible.