Punctuated equilibrium is a theory in evolutionary biology describing a pattern in the fossil record of long periods of equilibrium, punctuated by episodes of rapid development. It parallels patterns of external change in relationships as well as internal changes realizing personal growth and development, where intense periods of growth and change interrupt periods of stasis.
Life transitions are isolated periods of qualitative changes in life structure and ego development experienced at varying phases of life by each person; they are also cyclical, occurring every 7-10 years. Transitions become crises when one attempts to avoid the inevitable internal processes of change, growth and aging. There is an increased likelihood that a transition will become a crisis if a person has a history of turmoil and avoidance at previous life transitions. Unresolved issues surface and rebury, only to resurface with additional issues at each growth phase. Greater transforming-avoidance, coupled with the recycled and unresolved issues, yields crises of increasing severity over time. This is why many consider the Midlife Crisis to be the most tumultuous.
Though we are constantly recreating ourselves, the rate and degree are more significant during transitions. A transition becomes a crisis when a person avoids the act of reintegrating the lost fragments. There is recognition of a force toward change, coupled with fear of change.
The above list is comprised of symptoms, not causes. Aging does not cause midlife crisis--it is inevitable; midlife crisis is not. Since midlife crisis seems to be isolated to technologically advanced Western cultures lacking in ritual rites of passage, ageism is often blamed, but it is also not a cause of midlife crisis; rather it is an incubator, providing ideal cultural conditions. Symptoms are outward manifestations, not the cause of the crisis. It is in the extremes of these behaviors and their opposing difference from a person's stasis that we find crises.
There are many who witness the Cycling and Chaotic behaviour and conclude that Midlifers know exactly what they are doing. Since the behaviour cycles, there are pockets of rationale and clarity. Some are able to compartmentalize their lives, functioning at work and other activities away from the home. It is not that the Midlifers do not care, but rather that they must shield themselves from caring. They feel they must do whatever it is they are doing even when internally admitting it is wrong. They steel themselves emotionally; but they are not without guilt; rather I believe that for many it is the opposite. Their guilt is so immense that the burden is overwhelming. They are running from the demons within themselves and from the burdening reminders of guilt from the spouse, whether she is actively laying guilt or not. In addition, OWs add guilt by forcing responsibility for their happiness and success on the midlifer, and then by punishing him when he cycles between her and his wife.
Midlifers are not always aware of their actions. There is an awareness within each moment, but a global absence of awareness; this only becomes clear later. Driven by emotions, Midlifers are moment and self focused and often unable to link consequences and understand the relation of their behaviour to the external world. Their memory becomes fuzzy; though they may be aware of their actions during each present moment, in clarity they may not recall what takes place during fog and vice versa.
Large chunks of time are holistically blank. There may be a memory of certain events within those chunks, but the external relation to the world is lost. Events are not linked solidly to other things and thus may have no chronological placement. Time is a tangled string that rather than linear.