Hi, Es! Welcome back to the board! Good to see you posting again.
You said:
that it's because of Mom that members of the family act so weird around us
If you're wording it to her like you worded it above, then I suggest that you change what you tell her. I understand that you're helping her see that it isn't something she did, and that's good. But the fact is that it isn't something you did, either. It isn't about your choice; it's about their choices. By focusing her attention on you as the source of the problem, you may soon hear her asking you to correct the situation by giving them what they want.
I suggest instead that you explain to her that it is their decision to make, and that we can't make people act like we want them to, so we just have to love them even when they do things we don't like.
Of course, I only have your one statement above to go on, so I may not be understanding clearly, in which case disregard my comments.
COMF