I tend to think of defense mechanisms like the ones you describe as part of the way the mind learns to deal with disagreement between expectation and reality, only rather than updating on information about reality your mind protects your expectations from it. This is sort of like protecting your prior by manipulating new information so that the posterior doesn’t change much if at all. Learning how to break and live without defense mechanisms is something I view as the primary method of action in self-help.
I tend to think of defense mechanisms like the ones you describe as part of the way the mind learns to deal with disagreement between expectation and reality, only rather than updating on information about reality your mind protects your expectations from it. This is sort of like protecting your prior by manipulating new information so that the posterior doesn’t change much if at all. Learning how to break and live without defense mechanisms is something I view as the primary method of action in self-help.