Mother having extra- marital affair and harassing family. What to do?

my father had his house in bhayander which he sold and from that money and the money that my maternal grandfather gave him brought a house in the name of my mother for sake of love and affection, the payment demand drafts were in the name of my mother, but she didnt earn at that time, now my mother has an extramarrital affair, and wants to sell the house and kick my father out of the house, what can we do to survive, whole family is in my father's support and we have video and audio proof that she physically abuses my father, , my father even took loan of 7 lacs so that she can settle a beautily parlour, but now she is harassing us, what can we do? please help!