Im not really sure how to help you, im sorry
Maybe you could ocuppy yourself with someone else, like you said?
Or maybe you just need to hear what your friends/her friends are saying, from her?
I mean, has she ever told you herself that she doesnt like you like that?
I dont know if its just me but, if i had never been told by that person, then part of me (even if other people told me over and oevr again that the person didnt like me like that) part of me would still hope, that those people are wrong and that there is a chance they liked me.
Maybe you need to talk to her so you can accept the fact first, and in time youll be able to move on.
Without acceptance, it is going to be much harder because there may always be a part of you that doubts what your friends/her friends have said.
Sorry i couldnt help much, i hope you get everything sorted!