my boyfriend...

So me and my boyfriend moved back to where he is from which is a lot of states away from where I lived (also never lived out of that state) he has a close girl who's a friend. But we move here to starts planes for our future and such. I had a stone go threw ny system the first week we were here so I didn't go and hang out. Well I come to find out my boyfriend lost the spark with me but still loves me. But has it for the friends. So he moved in with his other guy friend. He "disappeared" for 36hrs (was offline and didn't talk to me or anything. He takes drugs semi-regularly) come to find out two weeks later that he had intercourse with her. I asked he about it and she's denning and everything. So I tell her off because she was also trying to give me relationship advice. My boyfriend uses my iPad that I wipped so he can use it to contact mostly me. So i took it away from him for about 24hrs. But me and him are working threw everything. But he still goes and comments on all the stuff she posted and talks to her. I don't know what to do. Because this week he had seen more affectionate andattentive towards me.. I know if I say he has to pick her or me he probably won't pick me. But I feel like he's my one. Can anyone give me an advice about what I should do at this point?