I miss him so much..?

(boyfriend)he was like the sweetest guy I'd ever met and then he got suspended for bringing a knife to school and then he changed a little bit but it started to become more and more noticeable over time...he used to say the sweetest things to me no matter where we were but then he only said them to me outside of school...whenever i would try to talk to him at his bench in the morning he would like blow me off and then starts treating me like dirt..after he said he would never do that just a few weeks ago.so of course i had to break up with him cause i felt like i didn't know him anymore and like i was trying to love something that wasn't there anymore...and i haven't seen him for weeks now and i miss him and his family really badly and i think I'm starting to go crazy..what should i do to get him out of my mind cause i keep thinking i see him everywhere i go. i need to see him or something ...please help me i don't know what i should do...