Your husband will have much better success if he detoxes with a doctors help. Please try to steer him in that direction. And detox may be a horrible experience. But stopping isn't nearly as hard as staying stopped. Can you suggest some kind of recovery program? AA? NA? drug counselor? Rehab? In order to stay clean an addict has to learn to deal with the underlying problem that drove him/her to use drugs in the first place. They have to learn new coping skills because for so long they have been using drugs to cope with life.
I wish him and you the best of luck. Keep posting.