Why Did She Leave Again?

When i was younger, my mother left my sister and I to fight a battle with drug addiction. When she came back she swore that she was staying for good. That was 14 years ago.now, I am 23 and she has left us again. Except now there are no drugs to blame. She left us,her husband, her home, pets, her business, and all that had at least at one point and time made her happy. Was she not fullfilled having all that almost everyone would want? Does she feel suffocated, restricted, is this the case? Are we not good enough for her? Granted, we are by no means perfect but whose family is? I know its stressful when business and family is close knit since it is a family business and she goes home to some of us, my sister and stepdad. but why couldnt she approach us about being unhappy? Is it our fault for not seeing it? Perhaps both? I guess all I can hope is that she'll come back. then maybe, just maybe, we can sit down for a while, let life pass by, and take time to listen to one another. GOD WILL IT SO.