I remember the months before my vertebropasty surgery when I was in constant pain due to my broken back. Bedridden, I kept thinking, "Well, now I have time to write" (although I could only write lying on my side, which was awkward). I was so frustrated with myself for my lack of output.
I had to accept that sometimes, one can try too hard to push through the pain. Sometimes it takes the time it takes, and "one sentence at a time" is the only way.
I feel for you, Marianne. But look what you've accomplished! Keep on keeping on.