Autumn -
I was almost in the same situation as you are in now, but I was lucky enough to get out.
The key is to take care of yourself FIRST. Try Al-anon and read the books Panther recommended. Educate yourself, and the decision, while it won't be easy, may become clearer to you.
Some people recover and some don't. You need to decide if you want to ride the roller coaster or not.
Your BF is definitely an alcoholic, and he's probably going to get worse. I'm sorry for the pain he has already caused you. I tried threats, promises, caretaking - you name it! Until I learned to let go, I was just as miserable as the alcoholic was.
I hope you will stay on this board - it has helped me immensely. Be strong and know that others are here for you. ((hugs))