My wife has criminal intentions.

I have been married for 8 years now. I have a son who is 7 years old. I had an affair before my marriage and I had told my wife to be that I don't want to marry you but my gf. I am a govt officer. As if being spellbound by my govt job and rich stature this girl and her parents threatened me of dire circumstances under dowry act and since I had an old widow mother and two very young sisters, one who was also hearing handicapped, I sacrificed my matrimonial ambitions and married this girl. I did not want to have sex with her after marriage but she created havoc in my house and so being afraid of being shamed in society I had sex with her and she became pregnant in the third month of our marriage. On delivery of my son I gave up all my intentions of leaving her and decided to have a happy life with her. But she had other intentions. She usually fights for jewellery and for the last 8 years is continuously abusing me using all sorts of incestous abuses. anyway I have tolerated all of it due to threats of dowry act and domestic violence act. I have married one of my sisters and the next one shall be married next month. However in the last 3 months I have started recording her abuses and threats to me. She says she wants me dead and she wants only my money and that she doesn't love me. She is also suicidal. She has taken depression drugs many times and I have to either take them out of her hands or mouth or get her to vomit. I have recorded all of it on audio. Recently I tapped her and her fathers conversations. She is also mixing some medicine in my food. I felt heart broken. I love my son very much. My mother is very old and I don't want to see her cry. I have sacrificed my life for my mother and sisters and am ready to do so for my son also. But why is she trying to kill me? I never asked her to give me divorce, I always said that you can live in my house and enjoy my money. Also she sends money to her father. I have video evidence of that as well as collaborated by her conversations with her father. And many more things which just indicate that she has criminal intentions. Her father is a crook who did some fraud in a bank. I want my life back. What should I do sir?