I hit that wall in '05, was ready to give up riding altogether; then I broke my R wrist, spent seven weeks in a cast.

While I don't recommend this as a way to get the fire back -- it worked for me. Haven't had a problem since.

One thing that worked for me, too -- no cyclo-computer. Forget numbers and performance. Just ride for the sake of the ride, get inside it, and experience it, Zen-like. Leave enough time each way, and just immerse yourself in the experience.