Mental illness via brainwashing is one form, yes, but if the mind is strong enough, it can be broken. Most is due to just plain ignorance.

. There are those genetically predisposed of mental illness, however, where certain stimuli will bring it out. Once out, it never gets put back in the bottle, so to speak.

Point is, I truly believe weak minded people are those predisposed and the constant need for acceptance and "likes" is very telling. Not being accepted for the facade they present affects them on a deeply egotistical way, to the point of anger.

A strong mind and willed person doesn't have those issues.