i posted about this back in january and received some wonderful words of advice and support from you guys, and realized i should post an update about what happened, if anyone was curious:
the wedding was last week and it actually went very well. i think i managed to not act too awkward, and i could tell that he felt awkward himself. he was polite but didn't try to engage me in conversation at first or any uncomfortable situations all weekend. my closest guy friend was there and he knew i was apprehensive about seeing my ex, and he was great -- he went out of his way to hang with me and see how i was feeling. on the last night my ex approached me and we did talk for about 10 minutes, but just general updates on our lives and our families, and there were a lot of people around us. i got the feeling that he was embarrassed and regretful about his past actions, although he didn't say so. it would have been nice if he'd apologized, but whatever. i've moved on and at least he didn't do anything bad like before!
thanks to everyone who gave me such great advice on this. i can't tell you how helpful it was. knowing other people had been through something similar, or even if they hadn't, just knowing what you thought about it, and also the general support you offered, was incredibly helpful and buoyed my confidence. so, thank you!