I Want To Stop Caring

I get upset when I think about the things that have gone wrong in my life, as most people do. but the more I think about it, maybe they didn't go wrong, maybe it was right. I fell in love for the first time, and all of a sudden it was over because I "wasn't the one" for him.....but I shouldn't be upset by that I should be happy that I can find someone who actually cares and loves me too. but it's hard sometimes, it's hard to pretend I'm not sad when I hear about him being with new girls, it's hard to be happy when I lost someone I loved. I wish I could just stop caring completely, but I'm not a heartless person. the one I loved is...I can't just stop caring and loving someone so suddenly. how can I stop caring.....