My wife is threatening me of suicide

I am married for 12 years and have a son 9 years old and have my mother age 61. From the very beginning of my marriage my wife fight with me and my mother with out any reason. Everytime her parents take her to their house after the fight. These goes on for 1 year. After that with family discussion we decided for a baby and she and her mother comes to my place. We had a baby boy and she was good at that time. Again she left with my son to her maternal home. I used to pay a amount of 10K per month for my baby as demanded by her. Now my son is 9 years old. She, her mother and my son is staying in different flat all expenses borned by me for last 7 years. I am staying with my mother. Now I found out that she is having calls with one of the flat owner in our residence for last 10 months. They used to conversed for whole nights. When I confronted her, she said that the guy is just a friend. And if I further continue with this, she will attempt suicide. And also the guy is calling me abusing me. We are staying separately for last 7 years. Now may be she is having an affair also. Can I opt for Divorce?