Earlier quoted context omitted.
> This is entirely wrong. You can suffer from depression (and anxiety) and attribute it to other things, such as personality traits. Many people think "that's just me" with those that know them thinking the same. For less acute forms of depression such as dysthymia, that's common. People can think they're entirely normal and they're just not good at certain things. My post explicitly says the hypothetical man is happ…
I don’t know of any mental illness that isn’t accompanied by intense mental distress
This does seem to be true for some forms of mental illness, depending on exactly how you define distress. For example, someone going through an episode of mania (such as in bipolard disorder) is typically subjectively extremely happy with their state.