need advice

So my bf and I haven't been together for much long but we liked each other for a long time and we didn't wanna get into a relationship because he's gonna move away soon and we decided we could do it anyway because we were gonna be shit if we didn't. Now I'm finding it hard to be happy without a reminder it's gonna be over soon cuz neither one of us wants to do long distance. How do I stop hurting and just enjoy it? How do I stop thinking about the break up before it's even happened? I don't really know what to do...