His ex is bff’s with his sisters.  She hates me guts and so my SO’s older sister also hates me.  This is the younger sister’s baby shower and she invited me (for the first time ever since I was “banned” from their events) I think to make peace because my SO was refusing to attend events where I was not invited (but his ex was).

While i appreciate the gesture I am getting crazy anxiety over being at a place with two people (ex and older sister) who have spent the last 2 years talking crap about me to anyone who will listen, including my SO.  I’ve been called racist names (“chun li” “fried rice”), called trash, been threatened violence if I come near them, etc etc though things have been quiet since the sisters’ dad died.  Though by the younger sister’s admission “they promised not to hurt me but they might talk” (????).

My SO’s kids will also be there and I have never been in the same place as their mom and them.  Their mom has made it clear that she hates me to the kids and that she doesn’t want them to like me.  So although the kids and I have a good relationshop I feel bad putting them in a place where they might feel divided in their loyalties and like they have to act a certain way towards me to please their mom.  I am also scared that if the ex sees them interacting with me positively she might make trouble for them or my SO.  

My SO says I am overthinking and have been promised “safe passage” and that I am being a coward and an asshole for not accepting his younger sister’s peace offering.  I was hoping he could relay the message that I had other obligations (it’s my sister’s birthday) and give her a gift/card from me but he says no.

AITA here?