There are lots of places to get help... check out the Friends and Family of Substance Abusers forum here.. also go to an Al Anon or Nar Anon meeting.
Crack is evil. I've been exactly where you are... you may want to check out a website called crackreality.com
I'm sorry and grieve for what you are going through. But the only thing you can do is learn, get support, and take care of YOURSELF.. there's nothing you can do to help him except to stop helping/enabling him. It took me a long time to understand that. If I stayed, moved out, helped him financially, gave him nothing, divorced him, stopped having sex with him.. none of it made any difference... he always continued to use. I moved out. He is still using. You are in a very vulnerable place... please get help for yourself. And stop listening to his promises.. stop trying to negotiate with him.. stop trying to get something rational from someone with self-imposed mental illness... sobriety isn't a negotiation (as someone told me here..) he either wants it or not. Also, you either want to help yourself or not.. My prayers are with you... I know this is the hardest thing in the world...