Divorce when wife pregnant

I am married and accidentally my wife 3 months pregnant. She is abusive/manipulative by nature I.e Narcissistic personality disorder (NPD) even during pregnancy period her behaviour didn�t changed she is more aggressive hurting her self sometime hurting me too using abusive language all the time. I am worried about my unborn baby due to her behaviour if some mishappening happen I.e. miscarriage it�s very difficult for me to live with her. I told about her behaviour to my in laws but they are not ready to listen anything some time I felt all this happened due to my MIL. Due to her pregnancy I am not able to take right decisions pls suggest what should I do. 1) Shall I file divorce on the basis of cruelty ( I have enough proof to prove this) but due to her pregnancy don�t want she roam around court room in this condition. 2) Sent my wife to her Home town and after Delivery will take necessary action. 3) continues live with her and record her actions and create more and more eveidence which will help me to take child custody in future. Also pls suggest which type of evidence I need to collect for infant child custody case,