In your message earlier you said:
I'm scared if I kick him out he will end up dead by drinking or running his mouth and get into a fight or fall down the stairs when he is drunk.
And if he stays, he won't do any of these things? Of course he will - and he will keep right on doing them as long as he continues to drink/use regardless of where he is living, or with whom, or under what circumstances - until he chooses differently.
It sounds like you have already done a lot for him and it hasn't done very much good. As much as you love him, you have to let him go and learn for himself. I know what it is like to be young and on your own with no parental figures to turn to - it is very, very hard. It is not worth your sanity or your safety to keep enabling him. Try contacting the local mental health department - they probably have some advice for you on where he can go.
As for you and your BF, Al-Anon is a great choice. They really know how to help you there. The first few meeting might seem a bit strange at first, but keep with it for a while and it all starts to make sense.
I will be thinking of you today.