Am I a total loser, every time i tried I fail in relationships.?

Well I am 25 and I have a problem. I had a 2 year relationship with my girl friend before she opt to marry according to her family to a total stranger. In the last days she always told me how great a person I am and its her bad luck that she is not getting me. It was practically devastating as she was my first love. But then time changes and after 1 year I finally got over her. Then I found this amazing girl in my office we talked for infinite hours on phone we met outside, we kissed and then she chose to tell me that she is kinda committed. Now I was shocked I asked her what is "kinda committed" so she told me that not long before meeting me ( 5-6 months) she was going through a bad phase of her life, she had an accident and she had broken up with her college boy friend. At this time a friend also from our office helped her a lot and eventually proposed her while she denied him but the reason she gave him was that she is not going to do it again after failing so miserably in her first relationship. So our boy being such a nice person told her that he'll wait forever, and in time she will change her mind. Now with passing of time they got closer and finally she thinks that she owes him too much and cant have a relationship with me right in front of him. She tell me that she is madly in love with me but there are things in life that are more important than love. Now yesterday I asked her to decide and stick to the decision. She chose him I deleted her contact and decide never ever to talk to her, now that may sound childish and immature believe me if I talk to her again I am going to fall all over again. i mean its they way she talks is what got me here in the first place. Now am I total loser for still wanting her and then again why does it happened to me twice. In both cases I was madly in love with the girl, totally faithful, totally committed and yet the answers are so similar - You are a great guy, its my bad luck, any girl would be lucky to have you, But sorry not me. is there something inherently flawed in me? I could go on rambling but really, seriously do need help.