Mom Knows it All

My sister is have marriage problems. Her husband has made some personal decisions that she is devastated by. Only my parents know what has happened. Her husband has not seen his kids in a while because she doesn’t want to see her husband. I was suggesting to my Mom that I am sure there is a way to allow him to see the kids without my sister having to see her husband. My Mom says “You just don’t know what has gone on and that just isn’t going to happen.” She has made similar statements multiple times to me about me not knowing anything and acting like I can offer opinions. It is true that I don’t know what happened. I do want to be supportive of my sister and help out and I feel like I can offer some ideas or different perspective even without knowing what happened. My Mom is not interested in listening to any ideas I have. I feel like she wants to be the authority on this and likes to point out that only she knows what the problems are and what is best for my sister. I have a story about my Mom that she always has to be right and won’t listen to anyone else. I feel like I never get heard and that she always shoots down anything I offer or even cuts me off from talking when I make suggestions. How can I change this story of her? It is so deeply engrained.

C – Mom says “You just don’t know what has happened and that just isn’t going to happen.”
T – Mom wants to be the authority on this and not listen to my ideas
F – unheard, rejected (I’m not sure how to pick one?)
A – I get upset, I try to restate what I am saying hoping we can have a conversation about possibilities, then eventually stop talking altogether. I feel upset about this later and keep thinking about it.
R – Don’t want to be around Mom or talk to her, avoid her, don’t invite her over