There are lots of power struggles in any relationship and balance is a finely tuned thing. When you take your vows you mean them but it's not until they are tested that you really begin to understand the impact of "In sickness and in health". You don't plan for a major illness and probably naively think it'll happen when you are both really old or happen to someone else.
When it happens it tests your resolve and the depth in which you made your commitment. I think when I first got ill we both assumed I would take a few tablets and I would be back to my normal bouncing self but we were horribly mistaken. 7 years of treatment later we are still living with the impact of my illness and I am still ill at times and not completely cured.
Decisions that we used to make together had to be made by my partner as I was demotivated and unable to think straight. He would do more of the housework as I was so tired I would need to sleep lots. He had to play with the kids more as I couldn't keep up or have the emotional space to deal with tantrums or hissy fits. And this would happen in patches of a few months at a time and it's exhausting for everyone really. I would get better and things would return to normal but the fear of relapse and more months of stress would be lurking around all the time and noone could relax properly.
Being ill for me makes me feel very disempowered. I get confused really easily, my memory is atrocious and everything takes more effort. My self esteem, or lack there of, compounds my lack of confidence, so normal tasks become very difficult. So then I give in and let my husband do more. It's ok to ask for help. But then I get resentful that he is being all controlling and doing everything and I am no longer the independent female I once was. It's almost like forgeting what you've learnt and feeling that you might never get your skills set back.
The feelings improve as the depression improves, but then what can happen is the behaviours that stepped in to deal with the crisis remain in place between husband and wife. The balance is still tipped in favour of the carer. And the patient for want of a better word feels that they are being treated like an invalid when they aren't. It's infuriating and a fight to get back to the balance that once was in place. More talking and negotiating has to happen, again. I often wonder if "normal people" have to work this hard at doing marriage.