Tiger,
You're afraid to leave him, right? But you're afraid when you're with him too , right?
You will know when you've had enough. It took me four years to finally reach my limit. We have not lived together for over a year, but we are still married. He has struggled with his recovery and has been in and out of re-habs and jail. Now I see him only while he is sober - that is the choice I made for myself.
My husband's doc is also crack. I call it "the demon drug". Remember that this, and most other drugs, can change this person and encourage him to do things to you, himself and others that he would never do if he was sober. I only say this because I want you to keep yourself safe.
I know it feels like he chose crack over you, but he didn't. He chose crack over himself. Believe me, he was only thinking of the high, nothing else, when he put that pipe to his mouth.
The friends here have a lot of wisdom to share so don't be afraid to ask for help. Come back often. Take a deep breath and take care of yourself.
God bless.