The DSM-IV Criteria for Borderline Personality Disorder:
1) Frantic efforts to avoid real or imagined abandonment.
2) A pattern of unstable and intense interpersonal relationships characterized by alternating between extremes of idealization and devaluation.
3) Identity disturbance: markedly and persistent unstable self-image or sense of self.
4) Impulsivity in at least two areas that are potentially self-damaging.
5) Recurrent suicidal behavior, gestures, or threats, or self-mutilating behavior.
6) Affective instability due to a marked reactivity of mood
7) Chronic feelings of emptiness.
8) Inappropriate, intense anger or difficulty controlling anger
9) Transient, stress-related paranoid ideation or severe dissociative symptoms.
I'm currently reading http://www.amazon.com/Stop-Walking-Eggshells-Borderline-Personality/dp/157224108X/ref=sr_1_1?ie=UTF8&s=books&qid=1259603146&sr=8-1 and the behavior patterns of both of my parents are so much clearer now. An absent father with at least 5 of these symptoms and a dependent mother with all 9. Their internal struggle has been described very well in this book by people with BPD, paraphrase:
"Without my relationship with X, I don't exist. I must keep X with me at all times, but I can't allow X to know how afraid I am. I have to push away X so that X won't reject me. But I have to keep X in order to exist."
It is a terrible cycle of idolizing and devaluing X (usually someone very close to the person with BPD), needing to keep X as well as to push X away, and relying one's identity on X while hiding one's self from X.
What's scary is that I went through that cycle as a child, preteen and teenager. As I fought for independence and grew during my adolescence, the cycle began to break down. When I moved away to college, I actively chose to stop. My physical distance from the sources made me able to separate my identity from the cycle and, thus, break it. Sometimes I still find shreds and they are getting easier to stop. My parents, though, can't separate the cycle from themselves; they have no distance, so they can't break out of it. And because they can't connect their behavior to reality, they don't think that they need help.
Now that I have complete independence, I will no longer put up with angry outbursts and berating claims. I'm responsible for my health and happiness and nobody else's. I can care about others, but that doesn't mean that I'm to blame when they can't take care of themselves.
My dad and I haven't had contact in 9 years; because of the time that has passed, I can better appreciate the good times we had. I'm currently trying to figure out what to do with my mom. I don't think that it would be possible to make a complete cut like with my dad, but I'm now able to leave when she begins an episode. I know that it's healthy to avoid statements such as, "You are unable to love another human being," and not to expect similar reasoning from someone who is motivated by fear.