I think this is where I belong.

[missmyfriend]

From the NAMI (National Alliance on Mental Illness) website, providing an analysis on mental illness:

"Mental illnesses are medical conditions that disrupt a person’s thinking, feeling, mood, ability to relate to others, and daily functioning. Just as diabetes is a disorder of the pancreas, mental illnesses are medical conditions that often result in a diminished capacity for coping with the ordinary demands of life.

Serious mental illnesses include major depression, schizophrenia, bipolar disorder, obsessive compulsive disorder (OCD), panic disorder, post traumatic stress disorder (PTSD), and borderline personality disorder. The good news about mental illness is that recovery is possible.

Mental illnesses can affect persons of any age, race, religion, or income. Mental illnesses are not the result of personal weakness, lack of character, or poor upbringing. Mental illnesses are treatable. Most people diagnosed with a serious mental illness can experience relief from their symptoms by actively participating in an individual treatment plan.

Mental illnesses are biologically based brain disorders. They cannot be overcome through "will power" and are not related to a person's "character" or intelligence."

A midlife crisis is more of a symptom than a cause, IMO. A majority of the people on this topic have described their spouses as undergoing a midlife crisis of sorts. This is only an armchair diagnosis but what also accompanies this declaration is that their spouses are in some state of depression leading up to the characteristics classified as a midlife crisis.

If they are undergoing depression where it changes their personality, it would be classified as a mental illness, although none of us are experts or fully qualified to say this as a surety.

I read the following from a site that provides answers to questions such as these. This is an opinion by a psychatrist and not necessarily generally accepted,

"Most likely, the DSM-IV would incorporate midlife crisis under the diagnostic heading of "Adjustment Disorder, Unspecified type", which is described as a maladaptive reaction to psychosocial stressors that does not fit one of the other adjustment disorder types (e.g., adjustment disorder with anxiety, adjustment disorder with depressed mood, etc.)...

One key feature of disease, in my view, is the presence of suffering and incapacity. The DSM-IV lists "social or vocational impairment" as a criterion in nearly all the major mental illnesses, and with good reason--otherwise, every perturbation of the person's emotional life becomes an illness. In addition, clinicians look for a recognizable pattern of signs and symptoms; a familial or genetic predisposition; an expectable or predictable course; and, in some cases, a predictable response to treatment, as general features of what we would call a disease, illness or disorder."

So no one can state definitively, including the experts, whether midlife crisis' can be considered a mental illness.

I would say it depends on the person and her symptoms may be attributed to either biological or sociological factors, i.e. it may be hereditary or she could be reacting to issues from her past.

Regardless, I understand what Bill is saying and believe that some people are making a conscious choice in their decisions while others are undergoing some intense stressors that their personality cannot overcome. Like holding your hand above a flame, you will do anything to remove it in order to avoid pain. I believe some of our spouses feel that they are in such pain that they will justify any action to ease their "suffering".

This especially applies to people that have changed their personality dramatically.