What can i do now?

Guys,
I joined to mylot just to share my sad event i'm running through. Please tell me what can i do. it's a real incident, and i don't know what will happen in future. I'm totally frustrated.. It's real and my fate is depending on it
I'm a 27, an Organization employee, and unmarried. I never fell in love before. But one of the girl from the same organization, came closer to me, she is 25, married and have a kid of 4 years old. She is nice looking, attractive lady with charming personality. She works in different project. But she is not happy with her husband, who is kindda cheater. She was just a familiar to me and i did not know anything about her family. I just could understand she was in deep sorrow. She used to meet with me once or twice in a month, which she did in her own wish.
One day she inform me about Her husband got married with another women and wanted to divorce her. From that time, I tried to support her as i can. From giving time to lawyer manage to giving good advices. But She could not forget her first husbands feelings.
At a time, she fell in love with me. Day by day, she came closer. By the way she stayed in her mom's house and her kid to husband's house. One day in a sudden she offered me to sex with her. I was not ready but can't refuse, as i'm also starting to love her. From that time we had sex for 7 times. though most time i was unsuccessful but she assures me it was no problem. From the third time she wanted to have less sexual relation as she had a guilty conscious for her kid and ex husband. So just for the love of her i reduce the rate to having sex with her.
Now there comes a villain, he is a friend of her, and she knew her from a long time. He is a rich merchant, and wanna marry her. Oneday i came to know that she agreed to engaged with her. He will also take her kid after marriage. But she did not told me nothing about him. I was angry but she said that she could do nothing about it. she needs a future. Now she stopped sexual relationship completely with me. She say she does not wanted to be fraud with her new relation. just think about my condition. i could manage to marry her. But...
My problem is i'm deeply fallen in love with her, and i tried hundred times for 2 months but i can't forget her. She wants me to have a life time friends relationship but not more than that. She also tell me she also can not forget me. She wants to introduce me with him and she will manage for my access in their home in future but no sex. She ofter quote" I still love you but i can't marry you. Our love will be one."
i'm about to lose my service/job. Now i lose faith on woman. I can't go for new relationship. I'm going to be mad. REAL MAD.
Please say how can i survive. i can't forget those. I did nothing wrong with her. But Why?
I can't sa it to anyone coz i'm a kinda friendless person but i need support. No one i can tell.
Please don't advice me like" You should not have done this"
but give some idea i can get back into life with or without her.