Hi! I'll be glad to help you with this issue.
I can imagine how confusing this situation must be for you. You are truly an incredibly kind, caring and loving person who is very sensitive to other people's needs and hurts. I'm being sincere in saying that and it is really very wonderful that you are making these efforts for a person who is so truly needy and has no clue how to fill her needs.
And this is actually the key to my answer to you that you need to consider and think about. I am a little hesitant to give psychological insights about her because I don't want you to take that as a recommendation to include her in your lives. You can't and you shouldn't. This is important. You need to take your husband's lead here. He's lived with her his whole life and he's learned how to protect himself. I need you to do the same.
She can, however, handle distant communication that's not too personal: email. That's a good opportunity for you to exercise all your kindness and goodness. But respect the boundaries your husband has set up and that she really needs.
Because you see, it's not that she's egotistical, full of herself. It's the opposite. She's extremely needy, has very low self esteem. She needs to protect her fragility at all costs. From everyone. From the waitress to her own son. She makes everyone reject her because she's so convinced she's only going to get rejection. This is a mental health issue and that's why I don't want you to feel as though these words are intended to make you try to help her. The opposite is true. You need to let her be. You need to treat this as her disability and work within it. Emails is a good tool, cards at holidays. Visits only rarely as you've been doing.
So know that your husband is doing the best he can to deal with a mom who has a disability. She has an emotional disability and you as her loved ones just have to accept it and hope she will choose to do something about it if and when she's ready.
Okay, I wish you the very best!
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