I think the identity crisis of midlife isn't really a crisis. It's more like finally having the courage — or the exhaustion — to admit that the person you performed for the last twenty years wasn't entirely you.
At some point in midlife you realize you've been answering the question "who are you" with a list of what you do. And then some of those things go away or change and suddenly you have no idea how to answer it anymore.
Stress and fibro have this relationship where each one makes the other so much worse. Today is one of those days where I'm very aware of how true that is.