Can't we all just get along

We used to get along when we were kids. But things changed just a couple of years back. When things weren't going well in my life, she was really nice to me. She would tell me about all the nice things that were going on in her life and well, I used to envy her life. Then when finally my life started going right, she changed! I couldn't figure out why! We started having big fights, and have never gotten along since then. I could never get over the things she has done to ruin me during the past few years. Maybe if she apologized to me, I would get over it. But it looks like she never intends to apologize for any harm she does to anyone. So I don't think we'll ever get along ever again.