Feel you there man. I been gaming since Doom days as well, the fire does die out every now and then. As some people have said here, my solution has been to:
-Fire up an old game that is familiar and I know I loved,
-do something else in the interim, can be anything from simply reading, to a different full-blown hobby. There's that many other things to do in life I'm sure you won't have trouble looking
(Music, languages, learning other stuff, building models, art, sports, martial arts, shooting, non-computer games, just too many!)
Then when you sit down to game again, because a new game is out or simply because you really want to, you'll find yourself fulfilled all over again =] Oh, and don't let your self-perceived diminishing skill as a factor (in case you are), that can always be overcome with a bit of practice. Most games these days have a pretty shallow learning curve.