This is a good page for descriptions of mental health disorders including Personality Disorders. Psych Central (Scroll down in this linked page for an explanation of what Personality Disorders are and a list of links to information about the various personality disorders.)

While many normal people may relate to some of the characteristics described in a Personality Disorder, note that in the description of what constitutes a Personality Disorder that the difference between a person with a Personality Disorder and a normal person is that the normal person’s personality "does not affect most people’s daily functioning to the same degree it might someone diagnosed with one of these disorders."

Keeping that in mind might help readers not to suffer so much from "medical student’s disease", where you read a list of symptoms and conclude that you and most of the people that you know are suffering from the ailment described.

Snicks