I've written about creative burnout before, but I wanted to discuss a similar issue so that the two don't get confused.
I gave birth recently. I experienced nausea from the six week point onward in my pregnancy. I don't know if you've ever tried to do anything while seasick, but you basically can't. Since then I've been enjoying the traditional sleep deprivation, also not a recipe for productivity. My point for mentioning this is that this is not burnout. If you are exhausted, sick, or injured, if you are going through a crisis, that is not burnout.
What's the difference? The advice for burnout is probably not going to help you. Yes, some burnout is so severe that it can take as long to overcome as some illnesses, but the strategies are different.
So, if you cannot be creative due to life circumstances, what can you do about it?
Be kind to yourself. I didn't playtest a single game for ten months. I'm struggling to make the changes I need to after I managed one playtest. It sucks, but sometimes you just have to recover.
Don't try to force it. You need a certain amount of mental bandwidth for creativity. I promise your ability to create will be waiting for you when you regain your bandwidth.
Practice silent free-flowing thought sessions. You may not be able to do much, but chances are you can sit quietly and let your mind wander. These sessions probably won't be productive until you regain your bandwidth, but the practice is good, especially if you don't spend much time with your own thoughts otherwise.
Enjoy whatever you can. Seriously, you aren't doing what you'd rather be doing, so you might as well enjoy what you can. I watched a lot of food channels on YouTube and read over 200 books on Libby.
You aren't a failure if your body decides to stop you from designing. You're putting in a different kind of work to one day get back to where you want to be.
I can't tell you how nice it is to get back to a "what I'm thinking about this week" post.
ShippBoard Games is a board game design blog that updates on weeks when I am less sleep deprived.