should i?.. can i?

..he loves me.. I love him.. he loves me.. he loves her.. what a mess! I am still stuck, I can't have the guts and will to do what I suppose to do. Should I continue fighting for what I feel and accept all the consequences of my actions? Or should I love back the one who loves me and forget about my feelings for him? Waaaaaaa ='( but... can I?