My partners sister (will call her SIL) don't get on, we're not even civil. We did prior to my LO being born but she out of the blue decided I was disrespectful to her parents by not letting them regularly babysit my LO when he was just a couple months old, started calling me all names under the sun and made nasty and vulgar remarks about my choice to breastfeed. I decided at that point I'd have nothing more to do with her, the things she said are too vulgar and nasty to even post here. My partner still speaks to her, and I've seen her once at a family event since the fall out, where we didn't acknowledge each other.
I'm fine with this set up as I genuinely want nothing to do with such a horrid person but my LOs first birthday is coming up and SIL has children who I would want to come to the party, and I imagine my partners family will expect SIL to be invited as well.
I'm struggling with what to do, I could be a people pleaser and invite her and have the memory of my baby's first birthday be tainted by the presence of someone I intensely dislike (and who doesn't like me), making me feel on edge and uncomfortable throughout the day, and keep the family happy. But then I will only get this day once, and I want it to be a happy and positive day to remember and it just simply won't be if she's there.
AIBU? What would you do? Don't want my partner and his family to be upset about SIL not being there but the way she spoke to me was beyond unacceptable and I really don't want someone like that in my life never mind present at such an important event.