cheated by a girl

hello sir, I met a girl in my building and she spent about two months with me by saying she is single. After one month I proposed and she accepted. After that we did kiss and love but not s*x. She always told me that she loves me. I told her I will marry her. After some time she left building and said me that, im going to gurgaon for job and I will live alone where only girls are allowed. I said ok. But when she went, she call me and told that she is living with a boy. She told me he is not her boyfriend but friend. I asked her is she loves me or not? But she still told that she loves me. Now she ignores me. She never call me, I call her but sometimes she switch off her mobile. And she never talk to me more than 2-3 minutes. Also she never talk to me after her office. I think she will be with her boyfriend after office thats why she does not talk. But I am very frustrate and I m going to mad now. Sometimes I think for suicide. If I die, who will be responsible for that? Can I file a case against her?