My gf's mom is the exact same way. We've tried sending emails, talking things out, but she always cuts us off, and anything that we say that she disagrees with, she just writes off as us being young, and immature, and rude. It's starting to seem like it's impossible to get through to her. She always gives this fake "Oh, well I understand..." and then continues the exact same behavior.
Since I'm coming more from your husband's side of this situation, I kind of wanted to add something about that. Obviously I don't know either of you, and I'm sure you communicate well, but just make sure that you talk to your husband a lot while she's there. I know that it's hard for me a lot of the time, because I don't want to get in a fight with my gf's parents, and it's not my place to say a lot of the things that I want to. It's hard, though, because my gf isn't good at standing up to her parents either, and by trying to make them happy, sometimes I feel like she's choosing them over me. Even though I know she isn't, it's hard when I just want to smack them upside the head, and she still tries to act like a happy, respectful daughter.
I just know how hard this type of situation can be on a relationship, so I would advise worrying more about how your husband is feeling than your mother. She can't make you do anything, can't make you move, can't make you leave your husband or your baby, even if she can make you feel guilty about not doing what she wants. Just remember that she's not in charge anymore. You have your own life, and your own family, and if she doesn't want to be a part of it the way it is, then that's her choice, and she needs to deal with the consequences. Not you.
Stay strong, and good luck.