Hey Movinon,
I agree strongly with Write and would add these thoughts to consider:
You can "call in sick".
If it will destabilize you or increase the threat level (as in, if there's any chance that seeing you might trigger increased aggression on his part, even if it comes next week)...I would also say: don't go. A few days ago you were terrified about what this person might do with his GUN, and you want to be in the same room, concert hall, restaurant? (I'm not getting it. Help me.)
Imho, NO celebration, ever, is "obligatory" enough to be more important than you safely and swiftly strategizing your life AWAY from contact with this person. Minimizing it at every possible opportunity and by every choice. For your daughter's sake. And your own.
I hope you'll decide not to expose yourself to him unecessarily. If that hurt you mentioned is a kind of ambivalence (yearning to see him in spite of everything)--you're not weird: so many abused people--even while trying to move on--do feel ambivalent, feeling the "tug" of being attached to the abuser. But if you are feeling that kind of feeling, I'd suggest: try to pull your ambivalence up into the blasting sunlight and give it a good, long, what-is-reality kind of stare.
You are a smart woman, Movin. (Now I'm really dishing out advice, hope it's okay.) I'd suggest: Ask yourself what you really want (in your life, not in the short-term). If you want consider a different decision about this event, maybe contemplating that very deeply could be helpful.
Sorry for sounding so opinionated but I am feeling an urge to protect you (maybe even a little, to protect you from yourself). Or maybe I'm having an unhelpful fixit fit. If this is unhelpful, please ignore it.
I don't know what the occasion is, but I know you and your daughter deserve to be exposed as minimally as possible to a poisonous dangerous man who is still fighting you and actively interested in damaging your life.
Sounds to me like having dinner with a rattlesnake. Even if you can't "see" him, won't you hear the rattle and imagine the fangs?
It's just what strikes me (no pun intended).
Be good to yourself,
Hops