Wife living in USA wants divorce from Husband in India

I have been married for 11 years now. We have 8 years old son. I came to US 5 years ago to study my masters and got a job and brought my son to US to live with me. My husband and I are not living together for more than 5 years now. We have had many issues between us. When I went to india to bring my son. He sexually harassed me and abused me and raped me threatening me that he will stop me from going back to US. He misbehaved with me in all possible ways. It was a mental/physical torture. As soon as I flew back to US with my son. I made it clear to my husband that I will never live with him. He quitted his job and demanded money from me. He had asked me to settle down all the money he spent on my education and I did settle down to him. Again he asked money from me . It’s been 3 years now. He hardly spoke to my son. He doesn’t even talk to his own son. I wanted to get divorce and legally end our marriage. But he is denying to file on mutual consent.please help!