Impairment 12 – Significant impairments in interpersonal functioning, b. Intimacy: Close relationships often viewed in extremes of idealization and devaluation;
Devaluation and idealization are defense mechanisms that the mind creates subconsciously to help it deal with overwhelming anxieties. These two mechanisms, as well as a combination of both, are often associated with Borderline Personality Disorder. Idealization occurs when we view people or ideals (such as a higher power), as perfect and having qualities that we can acquire through association in order to survive. We may idealize a friend, family member, or loved one. Devaluation occurs when we see ourselves or another person as flawed, worthless, or having exaggerated negative qualities.
With BPD, idealization and devaluation can alternate. This is referred to as splitting, which often leads to disturbing thought, emotional, and behavioral patterns. This can be detected in fMRI’s as excessive activation in the prefrontal cortex and the amygdala. Our defense mechanisms often function as opposites where we devalue ourselves and idealize someone else. MacGregor and others administered The Personality Assessment Inventory to identify participants as BPD or Antisocial. They then administered the observer and self-report Defense Style Questionnaire. They discovered significant overall group differences. BPD defenses emphasized interpersonal dependency and a tendency to direct aggression toward the self; whereas in APD, the defenses emphasized egocentricity, interpersonal exploitation, and a tendency to direct aggression toward others.
So what does this mean in plain English? This study certainly supports the view that most of our problems stem from a poor image of the self; however, how does this relate to problems with close relationships? Based on my own observations, I would say that we Borderliners tend to apply both idealization and devaluation to others and to ourselves. First, let’s deal with the self. We tend to have this ideal view of who we should be, how we should act, and what we should achieve. We have impossibly high expectations for ourselves, and whenever we fail to live up to those expectations, we enter a cycle of feeling unworthy and engaging in self-loathing and self-hate.
Now how does that affect our relationships? There is a tendency to place the ones we love on a pedestal. They are perfect, or rather, should be perfect, because we need them to be perfect in order to help us survive. Whenever they fail to live up to those expectations, we experience extreme disappointment which sometimes can come out in a burst of anger; but more often, we cannot afford to blame them and lose them, so we turn that anger against ourselves in acts of self-destruction. If we do show anger towards those we love, we are immediately overcome with profound guilt and shame which makes it very difficult to make any attempt to restore the relationship. In the case of extreme anger towards others, without the accompanying guilt and shame, I would suggest that this is not really BPD but more likely Narcisstic or Antisocial Personality Disorder.
 Presnak, Michelle D.; Olson, Trevor R.; MacGregor, Michael. The Role of Defence Mechanisms in Borderline and Antisocial Personality Disorders. Journal of Personality Assessment. 2010.