Matt I wish you luck. My post earlier on perimenopause was intended to give you some of the additional insight on what I believe to be a strong contributing factor on MLC (and yes many MLC sites mention hormones). See below on an interesting study that was just done in 2012:
"Recently, economists and behavioral scientists have studied the pattern of human well-being over the lifespan. In dozens of countries, and for a large range of well-being measures, including happiness and mental health, well-being is high in youth, falls to a nadir in midlife, and rises again in old age. The reasons for this U-shape are still unclear. Present theories emphasize sociological and economic forces. In this study we show that a similar U-shape exists in 508 great apes (two samples of chimpanzees and one sample of orangutans) whose well-being was assessed by raters familiar with the individual apes. This U-shaped pattern or “midlife crisis” emerges with or without use of parametric methods. Our results imply that human well-being’s curved shape is not uniquely human and that, although it may be partly explained by aspects of human life and society, its origins may lie partly in the biology we share with great apes. These findings have implications across scientific and social-scientific disciplines, and may help to identify ways of enhancing human and ape well-being."
What are feelings? They are brain chemistry. My wife had admitted to MLC and apologized for putting us through it, but felt it was the only way she could find herself. I have read various articles where the MLC spouse realized it must have been hard on their LBS because it was a long and happy marriage...who leaves such a thing?
The point of all this? There is more to it than past issues, or what you should have/ could have done. It is impossible to be everything to everyone. People have to have other outlets and not rely on one source for happiness. As long as you are not blocking her happiness, it is up to her to figure things out.
Anyway, this is not to serve as a distraction but rather another slice of the possible picture. I think the more well rounded/ open minded you are on the topic the better chance you have to cope with it.