You should tell her. If you keep it to yourself, you'll never know if she feels the same way and how happy both of you could've been. And if she doesn't, at least you know it and you'll be able to move on. I know it's not easy. I'm here giving you all my support, okay? (: Now go ahead and tell her.
Maybe it is stuck in your head because he cared. You always block people, so you don't give them the opportunity to show you how much they care. Have you ever thought that maybe he is worried about you? Perhaps he just wants to help and make things better for you (:
and for those who can relate to it... don't worry, at least you're not alone :D
You go, I'll go with you.