to make a long story short, my dad has a new wife, and she has a daughter, both of whom i despise and vice versa. they're invited to the wedding, but probably will not show. (if they do, only to spite me and draw attention to themselves, creating drama).
my aunt stepped up to throw my shower and wants a guest list. i made it without including dad's wife and her daughter and my aunt (dad's sister) said it's extremely rude not to invite them and is now considering not hosting it if i don't. my aunt totally knows the situation that i don't get along with any of them (haven't spoken in years, very bad blood) and it would be horribly awkward if these two did come, as everyone whose coming knows all the drama involved. i just really don't her there, especially on 'my' day. no need for two huge pink elephants in the room.
the question is, am i obligated to invite dads wife and daughter given the circumstances?