"A man's illness is his private territory and, no matter how much he loves you and how close you are, you stay an outsider. You are healthy"

This quote talks to the concept that health problem is an extremely individual experience, and even if somebody likes you and you are close to them, you can not totally comprehend what they are going through. It is a reminder that even if you are healthy, you can not fully understand the experience of somebody who is ill. It is a tip to be respectful of the limits of somebody who is ill, and to be conscious of the fact that you can not totally comprehend what they are going through. It is also a reminder to be caring and understanding of somebody who is ill, and to be there for them in whatever way you can. Ultimately, this quote is a suggestion to be respectful of someone's illness and to be conscious of the fact that you can not totally understand what they are going through.