We know Betty has been professionally diagnosed with both of these disorders, and I gotta say they seem bang-on. While I can empathize with her situation, I don't believe Dan was responsible for her personality disorders, only aggravating them. Having a medical degree, he should have known better. Do the descriptions fit him as well?
From Psychology Today
Narcissistic Personality Disorder
The hallmarks of narcissistic personality disorder (NPD) are grandiosity, a lack of empathy for other people, and a need for admiration. People with this condition are frequently described as arrogant, self-centered, manipulative, and demanding. They may also have grandiose fantasies and may be convinced that they deserve special treatment. These characteristics typically begin in early adulthood and must be consistently evident in multiple contexts, such as at work and in relationships.
People with NPD often try to associate with other people they believe are unique or gifted in some way, which can enhance their own self-esteem. They tend to seek excessive admiration and attention and have difficulty tolerating criticism or defeat.
Individuals with narcissistic personality disorder, according to the DSM-5, exhibit five or more of the following, which are present by early adulthood and across contexts:
A grandiose sense of self-importance
Preoccupation with fantasies of unlimited success, power, brilliance, beauty, or ideal love
Belief that one is special and can only be understood by or associate with special people or institutions
A need for excessive admiration
A sense of entitlement (to special treatment)
Exploitation of others
A lack of empathy
Envy of others or the belief that one is the object of envy
Arrogant, haughty behavior or attitudes
Histrionic Personality Disorder
People with this disorder are usually able to function at a high level and can do well in social and occupational environments. They may seek treatment for depression when their romantic relationships end. They often fail to see their own situation realistically, instead tending to overdramatize and exaggerate. Instead of taking responsibility for failure or disappointment, those with the disorder typically cast blame on others.
According to the DSM-5, for a diagnosis of histrionic personality disorder to be given, five or more of the following symptoms must be present:
Self-centeredness, feeling uncomfortable when not the center of attention
Constantly seeking reassurance or approval
Inappropriately seductive appearance or behavior
Rapidly shifting emotional states that appear shallow to others
Overly concerned with physical appearance, and using physical appearance to draw attention to self
Opinions are easily influenced by other people, but difficult to back up with details
Excessive dramatics with exaggerated displays of emotion
Tendency to believe that relationships are more intimate than they actually are
Is highly suggestible (easily influenced by others)