Oh my messed up world

I guess I'm just not cut out to be someone's girlfriend. It always seems that I'm doing something wrong. He's such a great person and I love him dearly. I try so hard to do my best. Maybe I'm not sensitive enough. Maybe I should just quit before I hurt him. He loves and cares for me so much that I don't want to ruin anything. I've never been lucky enough in my whole life to have someone like him. Maybe this is why I've closed myself off to people because I'm too afraid to hurt someone and do something wrong. Why me? Why can't I just be happy?