well i broke up with my girlfriend

I never thought that helping someone get a foothold in life would be such a treacherous endeavor. I have given everythingI can but the other person on the receiving end just did not know. In my life I can only name one person that has helped me the way I helped her. I even bought her a car. She eventually used that car against me and threatened to leave with it. She did it a couple of times but I would not have anything to do with it. I let her step on me and deamean me and my family. I was so wrong about this girl. She killed my self esteem and questioned my integrity I will not stand for it anymore