Seriously?

Okay. So theres this guy, he was my first love, we were best friends when we were little. Years ago he told me he once liked me, he knew i loves him but we were never together. We would always hang out and do pretty much everything. He even sometimes talked about the things we wish we could do together. Now were 16. I have a boyfrend who im in love with we have been together for almost 2 years. But me and the other guy. Its always been weird. We never talk, and when were near eachother nothing ever happens. The other day the teacher in our math class placed us beside eachother in a new seating arangment. And then today when we got in class. He started like flipping out on the teacher saying he wants to sit somewhere else. And when she didnt let him, he sat behind me anyways. I really dont understand. Like what did i do to make him hate me?