Can decay, interference and displacement theory affect long-term memory?

Question

If most of our personality is controlled by our long-term memories, can we forget those memories that control our personality, therefore forget most of our personality?

Answer 1

It's great that you're combining multiple theories in your question here, it shows higher level thinking about your subject. It also adds to the complexity of an answer. :) From a Psychoanalytic perspective there's no argument that we "forget" our personality based on not remembering or misremembering the past as it's influenced by other experiences and feelings.

Displacement likely happened at the time because it helped the person. If you get in trouble for making a mistake at work it may be easier to come home and be mad at your spouse than to accept and own the mistake (thus displacing your frustration on someone safer than your boss). Displacement can continue far beyond the instance thus becoming part of your personality.

Psychoanalysis uses the term "unconscious" to describe these areas of our personality that we are unaware of. For the most part therapy from this perspective is an attempt to make these aspects of personalty conscious. Awareness of one's defense mechanisms, regardless of the clarity of the original events, can lead to changing them.