You're coping with midlife crisis if you're agonizing over, "What have I done with my life?", "Why haven't I done more with my life", "What should I be doing with my life" or any of an almost countless number of variations on these questions.
The point is - you're not happy with yourself or your circumstance or both. And, you're unhappiness has reached a point where you feel compelled to do something about it. Good or bad. Smart or Stupid. Forgiveable or unforgiveable.