As the author says, "Knowing oneself emotionally does not mean being overly emotional."

Agreed. But drama queens do exist, and they are overwhelmingly female.

To me, drama = insecurity.
Drama makes good television but bad relationships.

Where does it come from? I believe drama is a need for control because life is scary for the drama queen.

In terms of relationships, I think it comes down to this:

When you feel safe, you let go of your need for control.
When you let go of your need for control, you surrender to the present.

When you surrender to the present, you feel so much happier.
The trick is to:

Trust yourself.
Be with someone who makes you feel safe.