In Hamlet, Claudius tells his wife "When sorrows come, they come not single spies, but in battalions." That often seems true in real life.
Within the last two weeks I have lost a friend and a family member. That makes writing difficult. You may have such times of sorrow, too - maybe not caused by deaths, but by discouragement and bad news: a rejected manuscript, loss of a job, illness, accident.
There's a lot lurking out there to ambush us, folks. So do you quit writing? Well, sometimes you have to take a pause. However, rather than just getting completely away from it, I prefer to keep a foot in the door.
So instead of writing new material, I take the moments I have (and sometimes there are very few of them) to read back over and tweak a small section of manuscript. Often I will note troublesome parts, bits that I worked over and still was not satisfied with. Those are the ones I revisit.
It helps. It helps take my mind off my troubles, and it helps the manuscript a little. Maybe it will or will not work for you, but it's worth a try. If nothing else, it's a time when I can read over my outline (no chapter is outlined at greater length than about half a page, single-spaced) and just let what is already done ferment a little in my mind and plant the chapter to come a little more firmly.
It's something to try as you fend off those battalions of sorrows that now and then attack us all.