Im loving a girl...bt she hates me with her whole heart..?

she dont know me...after few days i found her in FB..and i sent a friend request at least 4 times ....nw she knws me who i am...bt she rejected my request ..nw she is in other city for studies...and she has more frnds most of them are boys...since past 4yrs i am observng her evry activity...when she was in my city i was able to see her once in a year....i nvr stopped loving her bt im faild to tell her i knw its my fault bt i knw she is rejectd me even as a frnd....nw im trying to forget her bt is difficult for me...i knw that if we love somethng let it go free..i have pain that she is dnt likes me and shes might be get wrong persn....im observng her &frnds activities....she is in love with an other persn....why girls easly rejects whom are truely loving them and finds an other who are just using them for time p love...?is it her badluck that she is going far away from whom is loving her truely or..is it mine badluck that she is going far away from me..