I want her back in my life... Else I will end my life.

There is a girl in my office.I like her but still never told her. I became her friend and we were very close friends for last 1 year. She never had a boyfriend and I never had a girlfriend. I always acted like a boyfriend and she never opposed my boyfriend kind of behavior. I used to giver her roses and gifts and she used to love it. We used to talk 3 - 4 hrs daily over phone. We were in a kind of relationship but only thing was I never expressed this formally but she was fully aware of my feelings. Due to some failures in her career in her life she has decided not to keep any lover in her life but just to keep some friends( she wrote this in her diary.. but havn t told me). After that she is not talking to me. She is very rude with me. We had lot of fights. Now with some efforts I have established contact with her but her behavior is bad and there are a lot of difference between us now. I want her back in my life. Please help me in understanding how to do this.
She thinks that due to me she was unable to concentrate in her career. I can't discuss this with her because she never tells me reason behind this separation directly to me.I accessed her diary without telling her. I am hopeless and have decided to suicide. Please help.

I don't know what SHE is thinking, but I can tell you for sure: I would have absolutely NOTHING to do with someone who threatens suicide, and I seriously think you should get some professional help.

Be kind to her and give her space. The more you get clingy and needy, the more she will reject you. Be a man and leave her alone for awhile. Get yourself checked into a hospital for a little mental health vacation.