Love...It sometimes it lasts in love but sometimes it hurts so bad.?

So I dated this guy like 3 years ago. I fell in love and we dated for almost a year. Then one day it all vanished and he broke up with me. =( 3 years later, here i am...still in love with him dearly. Itsd almost the end of senior year and I want to hang with him and tell him how i feel. One thing of course is that Im not sire if i should tell him or not. I dont even know how to ask him to hang out, just the two of us. Most than that, I wouldnt even know where to beging to tell him how i feel. We went to Formal together this year back in January, and that was the best night of my life. I fell even more in love with him. I told him that night that he should make me the exception to his 'pact' of not dating anyone till college. He said he couldnt because he'll fail at the pact. I asked him if he even liked me and he said yes. I made him promise that after that night, we'll talk more and hang more, we did...for a bit. After a few days...we became separated and we dont speak to each other anymore. I even have him in my AP Calculus class, and worst of all, he is in my group and sits right next to me. I feel as if I was the one who made things awkward between us two. I really love him, I do. I know it's love. So... What should I do?