@MissingNotes: Maybe you'll be friends again someday but obviously not now. Sometimes it takes a few years. You can avoid him if you really want to. Make a point of it. If you want to go to a large social gathering, get a date to go with you and pay attention to him. You can even hire a guy from a dating or escort service if you have to. If It's a smaller gathering, just don't attend if you know he'll be there. You can also avoid him by arriving very early and then pleading another appointment and leaving when he arrives. Or having a friend call you to let you know when he leaves.
I know you'd like to be indifferent to him but you're not. So until you really, genuinely feel and can act that way, just don't see him. If you run into him unexpectedly, just be polite, only polite, and then leave as soon as you can.