"There is nothing to writing. All you do is sit down at a typewriter and bleed." - Ernest Hemingway

(For you youngsters out there, a 'typewriter' is what we used to call a laptop. )

Everyone has their own interpretation of what he meant by that, but here's mine:

If you can't write about what you need to write about, start writing about something else. Or about nothing at all. Stream-of-consciousness free writing. Use a 'dictate' function and talk at your computer. Grab a piece of paper and start doodling out a mind-map. Even just list what the items you need to be write something about.

Eventually you will find yourself writing something useful. It may even be relevant to what you needed to write about, which is great. But your writer's block will be behind you.

Incidentally, I forget to take this advice more often than not when I hit a wall. That's the problem with having a fatigue-causing illness (Fibromyalgia). It's too easy to let the fatigue talk me into taking the day off. You will find your own excuses for why you can just get back to writing later though. We all have some reason to procrastinate. We just have to avoid using it.
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Regards,
Eric Fretheim
Assistant Prep Leader, 2015 October NaNoWriMo Prep Challenge

"It is perfectly okay to write garbage-- as long as you edit brilliantly." ~C.J. Cherryh

“No, writing 50,000 words in a month is normal. You are not crazy. This is not insane.” ~Teri Brown