There are a lot times I am ill with Migraines, and some of my other medical issues that flare up from time to time. I live alone with a service dog, so he is my SO.
IF, I was married, I think it would be wonderful if my sweetie would keep the TV turned down low, accepted that I am ill, get himself something to eat, nothing with stinky onions, etc., and just come and check on me.
True love is saying your SO is beautiful even if she has a raw red nose, teary eyes, a voice that would make the Wicked Witch of the North sound good. How special would it be if he went out and purchased Ginger Ale, because he knew your Mom used to buy that to make you feel better.
"In sickness and in health" that is where this vow comes in.