Questions that might illuminate if there's a problem -
When's the last time you went for a walk?
When's the last time you were in nature for a while?
When's the last time you spent a day absolutely, completely relaxing?
How's your diet?
How's your sleep?
How's your sleep schedule?
When's the last time you had a vacation?
How much inspirational media have you been through in the last week - books, movies, audio, whatever.
When's the last time you hung out around or talked on the phone with someone really inspirational?
Beyond that - changing environment can bring you out of a funk, bringing a laptop to a cafe with no internet can be a great option if you can do some work offline.