The main way to tell if someone is insane is to see if they are psychologists. The problem starts when people take psychology in collage, but that does not make them insane. It is only when they become practicing psychologists that insanity takes hold of them and converts them into something that looks human.

And that that point they gain the ability to make people that come into contact with them also insane.
But this insanity is not visible usually to anyone but themselves. They know that they are insane. But they hide it in order to be able to continue in their profession.

While I realize that people do need guidance in their lives but going to insane people for guidance is a bad idea.
Psychologists and therapists  need psychological help. I wish them a cure and to get better soon. But there must be better places to go for life guidance than to sick people.

My own idea of where to go for life decisions ones own parents.  I have a basis for this idea. It is the fifth of the Ten Commandments. Outside of that ones siblings. And after that ones close friends.
There is a basis for this idea in Isaac Luria where we see that ones close family are actually integral parts of ones own soul.