How come I can't stop thinking about him??

Okay, so I’m 13 years old. and the guy I realllyy like doesn’t like me back. And every time I see him I cant even breathe and my heart is pounding crazy. I’ve written like 10 songs about him. I’ve liked him since 3rd grade. If I could, Id spend every second of my life with him. I feel like I love him. Every night I cant fall asleep because I can’t stop thinking about how much I like him and how he doesn’t like me back. I know im only 13 and shouldn’t be thinking im in love, but… I just can’t. Im always thinking to myself what can I do to get him to really like me? we’re friends… but its really hard for me to be good friends with him when I know I like him so much. he knows I like him. and for some reason my friend asked him if he’d go out with me and he said not right now cause me and my girlfriend just broke up. then she asked him if he’d EVER go out with me and he said Im not sure. FYI, I didn’t tell my friend to do this. and the guy I like knows that (please dont comment on how wrong it was for my friend to do this… I dont really like her). anyways… How can I get him to like me? How can I get over him??? pleassse help me. I can’t STOP thinking about him!! ever. oh and by the way… this isn’t zazz4life. its her friend. SHE WASNT THE ONE THAT ASKED THE GUY I LIKE IF HE’D GO OUT WITH ME. shes my neighber. im a little younger than her. but she told me I could use her account wenever I wanted to. so… just to clear up any confusion. thx people. I really dont know what to do.