Alcoholics, including me, don't seem to do well with ultimatums. It always fueled me to drink more, in a more secretive way. I had to make my own mind up to stop and that is when sobriety could finally gain a foothold. Luckily I have a patient wife. I hope rehab works for your husband, but if he doesn't even believe he has a problem, he has a ways to go in my experience.