Escaping from abusive girl friend and marrying another girl

Hi, I am at the age of 30, from Bangalore. I am having a lover for last 6 years. I am staying along in a rented house. She is staying in a PG. We are in a relationship for last 6 years. Last 2 years we are planning to marry, but my parents are denying as horoscope is not matching. Now I a realized that she is very abusive girl. She started scolding me and my parents in bad words. She found some of my college friends and office colleagues in facebook and pinged them and scolded me badly. Whenever we go out for shopping, she scolds and shouts infront of every one. If anyone noticed that and laughs at me, she feels very happy. I dont want to marry her, I want to come out of her completely and find new girl and get married. As I told I am staying alone in a rented house in Bangalore. She is staying in a PG. But she comes to me my house and we had a sexual relationship also. This happened because we were in a mutual understanding that we will get married. Now she is telling like she will complaint in police and make legal issues. Before that I want to know how to get rid of this abusive girl. Please guide me.