How can I get over my ex?

[Rain]

I want to start off by saying I'm 18 and he's 21. We've only started dating at the beginning of summer but everything happened really quickly because I was supposed to be moving in November. I told him from the start that I had to move but he still said he wanted to be with me. We saw each other as much as possible and texted each other everyday all day. We did this the whole time but by October he asked me to move in because he did not want me to leave so I tried out living with him. We didn't have any problems living with each other at first but the closer it got to November I decided to leave just to spend holidays with my family because they were making me feel guilty for choosing to stay so I talked to him about it and he was fine with it and I'd only have to be away from him for two months. He reassured me that he would stay with me and I could come back after the holidays but after I left he seemed really unhappy, usually he says he loves me everyday and texts me good night but he stopped doing that. A week after I left he dumped me saying he still wanted to keep in contact but he started ignoring me unless I asked a question about him sending my stuff back.. He told me all this stuff like he could never break up with me and that I was everything to him before but it turned out to be lies.
Now it's been a month after he broke up with me and I'm still crying over him.. I've been with other guys but I considered him to be my first actual boyfriend because he was the only guy I could stick to without feeling like I'd want someone else and deeply cared for. I still wake up hoping I'll get a message from him. I think about him constantly and I keep getting flashbacks of all the times I've spent with him. I know this all sounds really pathetic but I don't know what to do. I still can't get over it