Hello and welcome to Psych Central!

I don't think you ever did anything to deserve the treatment you are getting but not being your mother's puppet/slave, etc. It sounds like your brothers knuckled under, but you were able to grow up and establish your own life. And she didn't want that!
I doubt you could ever marry anybody that she would approve of. Obviously her reasons for rejecting your daughter and your husband are ridiculous.
I am no expert, but I wouldn't be surprised to find out that your mother has a personality disorder or two. She certainly doesn't sound normal to me, anyway.
I suggest you read the book "Toxic Parents." Meanwhile, please know that you will never be able to totally please your mom. I am wondering why your daughter is indicating she will reject you.
Have you had any counseling? I have had somewhat similar mother issues, and I found counseling to be my lifesaver.

Please don't let this woman ruin your life.