This is an on-going conflict with the FH and FMIL.
When we first started compiling the guest list, we did the customary thing and asked both of our parents for their own lists of family they'd like to have there. His parents are divorced, and his mom included her stepmother on her list. Problem is that FH has a horrible relationship with her since his childhood... Lots of verbally abusive/alcoholic memories and neglect. His grandfather and grandmother both passed away years ago, so it'd be an invite to only her.
FMIL still wants her there and chastised me for not sending her a save-the-date. She says we are being childish because everyone else got a save-the-date and that she should too.
I see her point, and it's in my nature to want as little conflict as possible ("can't we all just get along??").. but I also want to support FH.
Any good advice on how to handle this? So far he has explained how he feels, and I told her I want to respect his feelings about this but she's not letting it go and it's causing a lot of tension.
P.S. Our wedding isn't huge: 100 guests approx. It's not like all 400 family members are going except for her.
Help? And please be kind, I really want to do the right thing here.