I didn't know that the "blah" I've been feeling lately had a name, but after reading Nathan Bradford's post How to Deal with Revision Fatigue, I now know exactly what I've got.
A bad case of Revision Fatigue...dum dum dum!
--Disgust when looking at "the pile"
--Feelings of self-doubt
--avoidance of "the pile"
--filling time with anything else, but "the pile"
--general blah feeling within 10 ft of "the pile"
As you can see, most of the symptoms are related to "the pile" -- that partially finished stack of scratched out, added in, and completely rewritten words, that resembles a garbage dump. Someday, that horrid mess will be a book. And, it will be a better book for undergoing major surgery.
But, the natural consequence of doing a book revision is fatigue. The only cure is to complete the surgery, as painful as it might be.
So, if you too are in the throws of this dreaded disease, like I am, make sure you read Nathan's post. It's encouraging and there is a cure.
Just finish the dang thing!