It is your house. Get her out. (sorry so blunt, not much else you can do)
If it was that easy... Her son and granddaughter is the only one she has, and I try to respect that. Also My husband is against, he wants her around, he feels that since she brought up him alone, now is his turn to take care of her. I really dont know how to behave for her to understand that I am the mother, and I have the right to take part in my daughters education.
There is likely a reason she has no one else. If she is there, I am not sure if you can do anything. She is not terribly normal. Honestly, in my opinion you are having to make a choice between having mother live with you or daughters mental health. Within a year, she will be in the stage where moral development starts (4-6). Husband has same choice. I would protect kid, but that is up to you.
Should I make my husband choose - mother or me and daughter? Thats a terrible choice.
I understand how hard that seems and not meant to be cruel. I wonder what the consequence is of not making a choice. How do you see your life and daughters 2 years from now if things continue as is? And what would it mean about marraige and child if he chooses mother?? Give these things some thought.