Uncontrollable feelings

(Still) having feelings for another, even when you are no longer together; it happens. If you don't feel that way, at most, you're going to miss them (to an extent) and think about them. This is perfectly normal. This is how humans function. These are uncontrollable feelings.
It's not upsetting to know, that she still likes you. I get it and I'm "okay" with it. Because I know she can't control these feelings. But when she's hinting at you and trying to get you back, I begin to worry. I begin to doubt myself. I think of how much better she is than me, I think about what I'm doing wrong compared to her, I think about how it's all my fault that our relationship might not be going as well as you might have imagined it or not as well as you had it with her. The thought of this makes me think that you still might like her (maybe...? I wouldn't know). But I'm actually just afraid that you might leave me for her.
Maybe I'm greedy. I want you. I want you to be happy though, and to be with who makes you happy... But I really hoped it would be me. I really hope it is me.