I think you're on the right track; keep your H. in the loop, but wait 'till he gets home. UNLESS something really comes unstuck in the process and he NEEDS to know; keep an open mind about where you are as you go through this, and keep someone IRL that you trust apprised, too. Does your personal physician know about this? someone medically trained should surely be in the loop, IMHO, although I'll admit that I know nothing about coming off this kind of addiction....
Best wishes.
"Show me a completely smooth operation and I'll show you someone who's covering mistakes. Real boats rock." -- Frank Herbert