The stereotypical concept of the big singular midlife crisis has been debunked. Crises occur in every age span, and they are highly individual. I agree though that a crisis should never be wasted.
My wife is a psychologist (MSc @ university) and psychotherapist (system and family therapy, which is a modern & rather evidence based variant), and we've talked about this recently. According to their training, the stereotypical midlife crisis is a plot device for stories and not rooted in actual observation.
