Domestic violence after 18 years of marriage

I am being abused and mentally tortured by my husband and in-laws, My husband got into serious debts and to borrow money, he misused my signed blank cheques which I had given to him for managing family expenses. Now i am being targeted by the persons( whom I have never seen before) who lent him money. I am a college Professor and my husband (50 years) was unemployed till last year. I stopped giving him my salary which enraged him and he along with his mother started abusing me in all possible ways. They took away all my jewels given at the time of marriage and pawned it somewhere I dont know. He misused my signature to borrow money from various sources and left me penniless. Realizing that I will not support him financially he along with his mother drove me and my younger son out of the house. My elder son refused to come with me. Since this year he is appearing for his board exams, I came back after nearly 2 years. Everyday my mother in law gives me mental torture . What can I do?