How can you tell when someone is mentally ill versus just being different? For instance if someone likes to wear pink ties and yellow suits to work does that make them mentally ill? Maybe they know nothing about fashion but does that make them crazy?
I agree with Gerard. The best word for me is "Delusional" For if someone is mentally ill because their brain is producing sound and images that aren't in reality so they have the wrong perception about what is right and what is wrong.