Why am I still infatuated with her after 5 years?!?!?!?

you must really like her. Are you sure it's just an infatuation? thats how it used to be with me. The boy I feel in love with was always on my mind and it just killed me until we finally started talking again and I realized how much he had changed. he's still on my mind at times but less now. We've just both changed so much I just don't feel the same way around who he is now. So I guess the best you can do is either keep yourself busy so you have no time to think of her or find her and see/talk to her.