bf doesn’t want me to go to a party

one of my friends invited me to a Halloween party. I told my bf about it because obviously I’m not going to hide it from him and he told me he doesn’t want me to go. his reason is that there’s a guy that lives at the house (it’s like a college house so quite a few people live there) has hit on me in the past. but that happened in high school and we’re in our early 20s now, the guy has never been weird to me since. and everyone there knows I’m dating my boyfriend. and he doesn’t want to go because his ex will be there which I totally understand, they didn’t end on good terms and his ex has expressed before that she wouldn’t want him there either. I do really want to go because all of my friends will be there but should I just give up and not go? what would you do