Russ,
Slumps are an all-too-common reality in this business. I can usually get out of my dreary moods with new gear, new rooms or new songs. Take baby steps ....... use a raggae beat on some old standard that you know inside and out. It's so easy to adapt, once you get into it and the fresh sound just might snap you out of the cellar.
Reinvent yourself.
Buy a new suit.
Paint a room in your house. (Wives love that stuff!)Better yet - paint a CEILING. You'll be king!

Burn outs don't last too long after you recognize you're IN them. Now that you know the feeling ...... FIX IT!