If you think that there are no pilots with psychological issues, then you are delusional. Anyone can pass a psychological examination, especially for a job and passion for flying. Period. Same goes for cops, military, doctors, teachers, etc....
Just google pilot arrested and you will have a lot of reading to do in your future. remember Egypt Air, anyone? ADHD, OCD, depression, and STRESS are all types of mental illness. As for myself, I am ADHD, for me, there is no better job for my mental health than to be cabin crew. It benifits me and the pax for that matter. If everyone in high pressure jobs were fired, there would be no one left.
One in four people have some type of mental illness, so look at three of your friends, and if they seem fine, it YOU.