Separation Boundaries

My husband and I have been separated for about a month due to his alcoholism which caused several agressive incidents among other things. Today he was supposed to pick me and our 2 year old son to go to church. This morning he called and said he was throwing up all night and he wants a raincheck. I had a feeling he drank yesterday but its only a feeling. For anyone whos been in this situation, what kind of boundaries do i need to have? How long do i stay separated. Im so lonely and confused. Do i just take him back and just work through things at home? Im just tired in more ways than one.