You could always try some water skiing....
I think you have to step out of what you're doing, and do something you enjoy.
A long warm bath, some music you like, a show you like.... something that'll "break the cycle" that you're in.
you know? People say that taking 30 mins or an hour to do something else is wasting away your time, but realistically, you may get 3 hours less work done because of a grumpy mood. So by taking that 1 hour, you made up for 2
If not... here's the water skiing idea...