Domestic violence and mental harassement

My mother is getting mentally harassed and physically abused by my father. She is now 59 years old and he still beats her like anything. I am married and living in my in-laws home. Myself and my younger sister are always living in tension because our father doesn't treats my mother well. I always request my mother to stay with me but she is not willing to stay with her us(daughters) because she feels that she will lose her self-respect. He has injured my mom's head twice and she has been hospitalized but she didn't complain because she thinks that the family will be shattered into pieces and her second daughter's marriage talks will go in stake. But we (daughters) cannot see her being ill treated by our father because of us. He used my mom's innocence and had extra marital affair too. We (daughters) are independent now and we want our mother to be independent. Please let me know what legal action has to taken in this case against our father and we also want him to do settlement as my mom has served him for 33 years. She has suffered alot because of him. He doesn't allows her to live her life and always treats my mom like a servant.