People with a personality disorders have an inability to understand the consequences of their actions. Antisocials and narcissists seem to be completely deficient in understanding causation, whereas histrionics and borderlines understand it but project responsibility: It wasn't because I was drinking and driving, that tree was in the wrong place. They substitute reasons, instead of A causing B, suddenly C is responsible for B. They rationalize causation based on the façade of their present state of mind--which they may not realize is a façade. They are also skilled in offering reasons that are socially acceptable or understood. Consider the some of the standard neutrally blameless excuses for divorce.
Exposure of the incongruity is possible when comparing the rationalization with the behaviors. Denial enables them to believe in the validity of their reasons.
Some people consider repetitious behavior evidence of insanity. But is anything ever really the same? Conditions may seem the same; the butterfly effect begins with an unnoticeable flutter of a wing and yet it can change worlds. One stock IPO may appear to have identical conditions to another that soared, but something is different. Some receive a high from behavior with a risk of negative consequences; others in desperation for this time to be the one where things turn out continue to rely on hope without considering the changes they need to make to realize what they want. For most people experience is the great educator, teaching consequences through successes and failures. People with PDs fail to learn from their experiences that produce negative consequences and yet learn to repeat experiences that produce positive results--or results that are positive to them. Their exclusive focus on themselves makes them unable to realize the devastation their actions bring to others. The only consequences they fear are how someone reactively might damage them, they give no consideration if the perceived consequence is damaging to others but not themselves. Some--most likely APDs and NPDs--find the possibility of negative results a challenge and therefore exciting. When consequences do start to catch up, they seek escape so they can start over without facing the consequences.
Review Elisabeth Kübler Ross's stages of grief again.
These stages are not only for those dealing with the loss of a loved one to death, but may also be experienced in other life circumstances. MLC begins with Separation and progresses through to Liminality, Rebirth and Reintegration. These are also the stages of a midlifer whose transition does not become a crisis. Why do some experience a crisis? Why are some crises more severe? A midlife transition may be a difficult and painful experience without approaching crisis levels, but what makes some tip the scales?
It is not the fault of the OW. Personality Disordered OW or not, an MLCers' crisis belongs to him and there is nothing a spouse or anyone else can or should do to stop it. But an OW with a personality disorder explains many of the behaviors, and may explain why some linger and seem stuck for long periods in Replay and Liminality.