@DFOD thank you for your long response, I appreciate it so much. I know. I felt this nervous the night before the family holiday we went on before Christmas. I still lived with my parents at that point. My DM was defensive of her at first and we argued over it, then she came to give me a hug afterwards and said she understood. My worries were confirmed and the time on the holiday honestly ruined my Christmas even though all I/we tried to do was grey rock and grin and bear it, never called her out, she belittled me and the behaviour was honestly just so terrible but so subtle at the same time. It really knocked my confidence and made me feel rubbish.
I do think you’re right as although the behaviour is covert, she does like the attention on her and will probably feel empowered by that. She feels threatened by her SIL and makes it clear she doesn’t like her too. I don’t know how possible it will be to keep away from DSis or only be around her in the presence of others. I really hope I can at least manage that and stick to the other bridesmaids.
I have this horrible gut feeling that she is going to try and do something to come between me and my partner, like make something up that either he or I have done. Gosh, do I sound paranoid there? She loudly said before that her wedding is the last wedding our nan will live to see - which I was horrified by. Nan is elderly but has grandchildren (including me) in long term relationships. She is just very entitled and it’s almost like she doesn’t want me to be equal, I think that’s why she doesn’t like my partner. Everyone else in the family gets on really well with him, aside from DM who has been convinced by my sister that my OH is the reason I took a step back and that he is the controlling one. That in itself is really messed up. She has pretended in recent months as if he doesn’t exist. We both know what she is like and obviously have a house together but I do have anxiety and I am really worried because she is very socially clever, outgoing and will stop at nothing from emotional guilt trips to even going as far as to push my face to the side when I didn’t want to take a photo with her.
I am most concerned I’ll want to leave. I’m not drinking for that reason (not that I’m a big drinker anyway) but if I do want to leave, I can’t once we’re there as I can imagine it would be spun around as me that had ruined her day. We are staying two nights. She has already said that I’ve baffled her and affected her views of her own wedding.