@disguisedlamb This makes me crazy. I am one of those people who gets SO damn sick because of autoimmune stuff that causes me to flare up and get super inflamed and fatigued and even the smallest, gentlest chores and activities wipe me out. It varies from illness to illness so sometimes I can push through but other times I'm totally couch ridden.
My husband can handle about two days of me being in this state before he decides it's been long enough and it's time for me to start pulling my weight again before the house is a mess. It's really damaging to my trust in him to be honest. It makes me feel like my worth in the relationship is defined by how productive I'm being at a given time.
You need to sit down with your wife and really talk about this because I think it can put you both down a path of resentment. Explain that couples go through periods where each is doing 50/50. But most of the time, you're in a flow state where it goes from 70/30 to 40/60 to 90/10 to 20/80 then back to 50/50 again. She needs to be supportive of you during those times that you are operating at 10%.
The other thing is that she probably thinks she could do a "better" job of childcare when she's sick. And maybe she's right. Maybe she could push herself more, be more engaging, etc. But you are different people with different abilities and that HAS to be okay. Maybe you have further limits than she does in other situations. The point is she needs to trust that you are doing your best. Instead of saying "WTF why did you watch so much TV" she should be saying "Oh gosh you watched a lot of TV you must really feel like crap."