How Much Should the Well, Caretaking Partner Share with the Ill Partner?

Here's a question that some comments caused me to ponder:

How much should the well, caretaking partner share with the ill partner?

The ill partner is suffering from body pain, or fevers, or headaches, or cancer, or from the side effects of treatments. He or she has had to give up full engagement with the world and can no longer do his/her old job or hop into a car to visit friends or go to the movies. Spontaneity has been derailed by the medication regimen. Freedom has been shrunk to fit within the boundaries set by the illness. And, as if this weren't enough, the ill partner is, understandably, depressed over his/her symptoms and limitations.

The well partner has assumed more and more of the couple's dealings with the outside world. He/she does the household chores, negotiates with the insurance company, oversees the kids, tries to stay on top of bills & budgets, and goes to work. And, as if this weren't enough, he/she also takes care of the ill partner. He/she helps the ill partner with the daily living activities the ill partner can no longer perform solo. This can include everything from monitoring medication to waking up 4 times a night to help the ill partner get to the commode.

The well partner is physically exhausted and emotionally bone dry. He/she is so busy every moment of the day that he/she can't stop to spare a tear for his/her own sorrow and worry. In those limited moments when there is a brief respite from the storm, he/she starts to feel choked by stress. It is a physical sensation -- as if all the air has been pulled from his/her lungs.

The well partner doesn't know how he/she can go on another minute and at the same time, he/she knows he/she will find the strength somewhere, some how, to continue. He/she doesn't talk to the ill partner about his/her depletion and anxiety because he/she is afraid the ill partner can't bear it -- that it would push the ill partner over some ill-defined edge into full bore breakdown.

This scenario may fit yours, or it may not. Whatever your circumstances are, I'd like to know:

If you are the well, caretaking partner, how much do you share with your ill partner about your situation? What are your choices based on?

If you are the ill partner, how much do you want to be protected from your well partner's state, and how much would you want him/her to share with you? What are your wishes based on?