How to get divorce when wife is not ready for same

We married in Feb 2009 and it was arranged marriage. After 2 months of marriage she started showing her character. After 4 months she had miscarriage due to medical ground and I spent approx 1 lac for the treatment. In Feb 2011 she consumed half selphos in anger but she saved finally. There was no police complaint. After that I sent her to parents place and their she lived for 7 months and I had very less contact during that time and whenever we talked she continued her tourturing and threateing that I will commit suicide again. When her parents approached to take her back I consulted a lawyer and as per his suggestion I filed a petition in Lok Adalat regarding her character and later we had agreement that now she will stay normally and will not do same as past. I have a copy of that agreement with me with court stamp. She was normal for sometime but started same behaviour again and in between we have a son in Feb 2013. We visited psychologist as well but she stopped taking medicines after 3 months of treatment with reason as no benefit. I have all the prescripttions. Currently she continues abusing me and my mother with foul languages and also she shows her ange with kid as well. I talked to her elder sister as well for solution and she also agree that my wife is very rude and its next to impossible to make her understand that you are at fault not your husband and mother in law. I have all the recordings for the conversation I had with her sister. Now it is getting impossible to stay with her as she continue threatening me and my mother that she can do anything. I want to proceed for divorce and also want my child custody as she behaves very rudely with him as well. Her family is not supporting her. Please advise.