Well I think you might be selling sobriety a little short. I think that you will discover as you get some sober time under your belt that having to quit drinking is far from a curse. In fact, the hell that my life was has largely disappeared since I got sober. Looking back I'm not sure why I put off the decision to get sober for as long as I did. It seems sort of silly, why did I continue to self-sabotage for so long when a manageable life and a shot at happiness was just as simple as putting down the bottle. FWIW, I too am single, no kids, in my twenties, no real responsibilities, but that makes my sobriety all the more important: we are both at a unique time in our lives where we can really focus on ourselves without the burden of taking care of a family or a career.
I think once you give it some time you'll discover that the love affair was over a long time ago, and you'll wonder why you didn't leave your mistress sooner.