I really do sympathise. But, based very much on how it was for me, can I ask you:
"It isn't so much the taste, although I did find myself looking sadly at a gorgeous Shiraz and some Dolcelatte and knowing I couldn't indulge in one of the most perfect marriages in gastronomy" - if you drink throughout a meal (or evening) what state is your palate in by the later stages of the meal? Do you HONESTLY appreciate "one of the most perfect marriages in gastronomy" or is it pearls before swine by that point?
"it is the growing exuberance, lightheartedness and joy that I find I miss in a crowd of good friends" - you say you miss this, but when was the last time you actually had it? I ask because personally, if my drinking had stayed like this, I would still be doing it and certainly wouldn't be looking to cut down or stop. I certainly remember that feeling as an undergraduate - by the time I was 27, things were very different ...
"I suppose what I'm saying if I were honest is that it's the effect I miss" - do you really miss the actual effect, or, like me, is it a half-remembered, once-upon-a-time effect that you miss; that you already missed while still drinking, in fact, and that you were chasing in the hope of recapturing?
Again, looking back to those golden days, how many times then did you need to swig it from the bottle on the sly? Is that really part of the good times?
You're doing really well and it's great that you're getting honest - but the bottle will lie to you, given the chance, and it's that that threatens you, much more than the contents.
I don't know if you're happy yet to use the A word, but I am about me, and I like to remember, "the alcohol's in the bottle, the ism's in me."