I agree, tough to really answer. For years I had a vague awareness that I didn't drink like everyone else I knew. My drinking had...an edge to it, for lack of a better word. A few times over the years I'd vow to ratchet it back a notch, and a couple times I took "breaks" from drinking. But eventually I kind of gave in and just tried to mitigate the damage instead. For example, I quit going out to bars so I wouldn't have to drive.
But back in October 2012 I finally got so sick of it that I no longer wanted to live if living meant being a drunk. Somewhere around the 3rd or 4th I took my last drink. Since then I have not had a drop, so no relapses at all. Maybe it's because I just got burned out on it to the point where I gave up on booze. Obviously if I was foolish enough to drink again I'd back where I was. But I have no desire to pick up a wine glass again now.