Mental insanity Grounds for divorce

I have been married for 2.5 years now and have 2 year old son from our marriage. My wife has genetic history of mental disorder ( He Mother who was kept in asylum for some months). I was aware of her mother condition however was not aware if this can be passed genetically. Now the evidence of her disorders have started showing up by use of abuse to my parents and me. I am worried about my son as she drags him along to her mothers place every time there is a fight which is now become extremely common. I am still confused about her condition as she is working lady who behave normally at her office. She has prejudice about our entire family, who take care of our son during our absence at home as we are both working professional and treats them as servants. She is undergoing the treatment for the above and the doctor has confirmed verbally that this is genetic disorder and will reflect in her life. just wanted to know, if I can file divorce on the above grounds and can I get the custody of our son.