I'm lost

So I've been having this crush to one friend of mine. We've never talked to each other since he only hang and talk to his friend that has the same background with him. But we surely look to each other oftenly and it's not rare for us to actually locked eyes and quickly pretend to look away and others. One day on the library, he sits right next to me and I was all happy about it. I was too carried away with the thing I'm doing at the time and when I look up, he was already talking to this one girl. What I know is that my crush doesn't talk to any girl (from my friend that's close to him) and suddenly this girl sits next to him and laughed together. So I was a bit hurt at that time and tried to ignore him. So I did. When we met at the hallway, I'll pretend to not see him and keep on a poker, pissed off face. Surprisingly, when it was on the other time, he was the one doing so to me. I was confused. I'm the one who's suppose to be pissed off, not him. And then after that library thing, I've never have the intention to look at him anymore. We've never locked eyes or anything because I tried to ignore him as much as I can Though, this girl that he talked with on the library turns out to be our senior, and after that, she always glared at me everytime we pass through each other. If I come to the library and she's already there, she'll whisper things to her friends and her friends would also stare at me. I'm confused. What did I do? This morning when I come to the library, he was there. Only that he sat on somewhere back that I didn't see him at first, but as the teacher told us to leave, I saw him and he was looking at my direction. His spot where he was sitting at was actually a very good spot because he could see me from his table but I can't see him. So as the students were dismissed to move to other labs, I choose the closest one to the library and quickly put my things. The unfortunate thing is, he talked to that girl again and this girl changes her expression as she saw me. She turned pissed off and anything while my crush put on his poker face. Well he's a cold emotionless guy so I don't really know what he feels or anything.. So what do you think I should do? Should I just move on or what? I really can't get him out of my mind, but his 'friend' was really freaking me out.

Help me out, please Thank you! <3