You must always be puzzled by mental illness. The thing I would dread most, if I became mentally ill, would be your adopting a common sense attitude; that you could take it for granted that I was deluded.
There are two big forces at work, external and internal. We have very little control over external forces such as tornadoes, earthquakes, floods, disasters, illness and pain. What really matters is the internal force. How do I respond to those disasters? Over that I have complete control.
I've seen people recover physical abilities, yet never get over emotional trauma after a serious accident. I've seen other people overcome the psychological and emotional trauma of a serious illness even though they may never fully regain their physical capabilities. Which is the greater healing? Which is the better recovery? If I had the option of choosing between a mediocre life with eyesight or the life I have today, even though I am blind, I'd stay blind and keep the life I have.
Money is the most important thing in the world. It represents health, strength, honor, generosity, and beauty as conspicuously as the want of it represents illness, weakness, disgrace, meanness, and ugliness.
Romantic love is mental illness. But it's a pleasurable one. It's a drug. It distorts reality, and that's the point of it. It would be impossible to fall in love with someone that you really saw.