Hi all. Pull up a chair

Some of you might remember my post from a couple of weeks ago...my SIL (partner's sister) had not asked me to be in her bridal party and I felt like I was the only one excluded as every other SIL- not sisters as she doesn't have them; but her other brothers partners and grooms sisters- were all asked.
Obviously this is her decision, her wedding, but the secretive way it was handled was difficult and the fall out has not been good.
Some members of partner's family have (unknown to me at the time) blamed MIL and tried to defend me. MIL has huge problems with me for a couple of years, massive back story here regarding my MH and arguments between her and DM when my DD was a toddler.
I've seen MIL a few times since and she obviously feels some kind of friction as she has told me exactly what she thinks of me and my family, told me I need to act as if my parents are dead
and generally ranted at me. All in front of DD. Generally a huge mess.
I got added to a chat group by another SIL (not bride to be) about hen do details. She is having two do's. Won't go into full details due to outing but it is in a place abroad I have been to several times and will be quite costly.
I haven't replied as yet.
Reasons not to go:
I'm generally not wanted by SIL (bride to be) who has not spoken to me about any of this directly, I imagine people won't want to share a room with me etc, the cost, being away from DD, MIL might start shouting at me after a few drinks.
Reasons to go: Might smooth things over, show I am making an effort and not bothered about being the only one not involved in wedding party.
So YABU- I should attend
YANBU- I should not attend.
Thanks so much!