Me and my best guy friend got in a fight?

it's a long story, but we were dating last year and he broke up with me for this one girl. i was fine with it for awhile, but then he would mention her on the computer and i got mad and refused to talk to him. i was fine over the summer, but i had this dream about him and ever since i keep thinking back to when we were friends. i see him in the halls after lunch. but i can't just go over and say hi. it would be way to awkward. i want to be friends with him again, but i don't want to date him again. what should i do? serious answers, and no rudeness. thank you!