How to get over a break up?

I recently just ended a relationship my  ex boyfriend that I dated for over a year. It hurts so much, I put so much into our realationship. I cut off friends that I barley hangout with anymore, I concentrated on him more than I did on school, which was a huge mistake. Anyways we broke up because of our constant fighting, we both knew it wasn't going to work anymore since our happiness was slowly going away. He was my best friend, I spend everyday with him so I miss him even though we fought all the time. How do I get over him? It seems like I'll never move on. He was also my first everything, boyfriend, kiss, sex, everything! I'm 20 years old and I feel like I'll never have what I had with him and that tears me apart. I would call him but I know that's not healthy. Will I feel like this forever? I'm going crazy!