Sometimes you must treat your writing like a lover.
When things have turned predictable and stale, when sex is still had but breathless anticipation of it is not, surprise can be the cure. Corner your other in the kitchen, the foyer, behind a tree in the backyard and instigate a little “quick and dirty.” It is amazing what will come.
(I jumped my writing last night right after dinner and had a rowdy and productive romp with it on the living room floor. It was just what we both so needed.)