I love you,but I cannot

why is it so hard to love one?! I have two times that I wanted to give her all my heart. First time is in sec 3, the second time is this week. Now I fail. I failed to grasp her heart. I fail to deposit my love, my hope on her. Also the first time. When I have the hope and was in love, I could not sleep;when I lose the Chance and hope I have not appetite to eat. Today, I gave her my gift and suprise. She replied: hope that you can find your own love and happiness. Oh my goodness, It is very clear that she didn't accept my heart. What a difficult job of running after a girl it is!!!! What should I do? without her, do I have the motivation to work,study and excel???????

I believe God.I know that it is the special design for me. I know this is the protection that god wants to provide for me. yeah, everything is in his control. Serving him is the main task for me in my life. I always say I need a person who I am willing to work hard for. Actually, I have. I have god. I can do the thing to glorify him. yeah, sin,the sinful nature, don't follow me any more!Holy Spirit, please fulfil my heart and let me see the great grace and love for me!!! Amen!!!!