Similar to frog, but I also felt the physical symptoms - headaches, dizzy, vague, shaky, dry mouth. It is an horrendous feeling, but worth it in the end. Rather than limit his cigs, would your DH try gum or patches? I found the gum great as it also gave me something to do with my mouth. Now just need to break the addiction to the gum, which I've been chewing for about 5 years!!! At least it doesn't contain any of the nasties besides nicotine and doesn't passively affect the health of anyone around me! I couldn't have quit without the gum, it took the edge off the craving and the physical symptoms.

Good luck to your DH, it really is worth it!