I need to get over a guy who never liked me ASAP what to do?

Here's the story. I've tried eveything! This guy is my best friend. I meet this guy freshmen year of highschool. I liked him like from the start. he started talking to me and we got really close and evrything. We have never gone out like together (dating) or to any place together in general. He would tell me all this stuff about his life and his feelings for one girl. I was there for him throughout 3 out of his 4 of his relationships. He trusted me alot. But the 4th time I couldn'tdo it anymore. I had a friend whom I meet freshmen yr and she knew I liked him.Yet our sophomore yr she went out with him. Knowing I still had feelings for him.BTW freshmen yr I told him my feelings and he acted like a surprised. I need to get over him. But it's impossible. Now in my junior yr I still like him. This is the horrible part yet our dads are from the same small town and they might have grown up together. So even when I'm older I will have to see him. He knows my whole side of the family from the little town. He is a big flirt. I actually thought he would like me. I waited too long. 3 years and I can't do it anymore. My friends tell me to get over him I tried. At one point it worked and it did. But then when this upcoming school year started my feelings came back.IDK what to do. Any suggestions?