Wow, AChapie - that's a huge red flag.... It just makes me wonder what else he's done in his 13 years of "sobriety." It's not as if he just decided to take an "extra pill" which is bad enough (and typical of us addicts), but he deliberately set out to get really high, even dangerously so.
The other thing that bothers me is that he seems to be drawing you into being responsible for him staying on the straight and narrow by telling you so "he won't abuse any more." Not fun for you and not a good strategy for him.
If he's not at a meeting talking about his relapse immediately, I would be very suspect. Sorry to have to say that, but what he did is pretty serious.
Check out the Family/Friends forum, too. Hugs and prayers..........