I know it will be hard but like the others have said, you need to stick to your guns. Your soon to be bigger family need space and a healthy environment to grow and quite frankly, your mother is not going to help that in any way. I am sorry you can't have her be a part of your life right now. I know it's tough after all the time, energy and love you gave her, but you need to think of your husband and new baby right now and not her.
I know you can find the strength to keep to your guns. A mother's love and will is a strong thing indeed.