Imagine getting rid of all your possessions and wealth, moving somewhere that you have no support network, not talking to anyone you know, and living on the street (going hungry sometimes, facing the elements, not being able to shower regularly, wearing holes in all your clothes, ...). After 5 years, what do you think the chances are that people will consider you “mentally ill”? If you want to make the experiment more realistic, imagine also suffering some trauma that causes you extreme amounts of anxiety for a while such as going through a messy divorce with a scheming narcissist, having your family disown you, getting severely physically assaulted, or killing several innocent people.

Many “mentally ill” people were formerly considered “sane” within the bounds of social norms, but even the best prepared can fall on hard times, and being homeless and socially isolated is really hard even for the mentally strongest.