GA, I hope that you will continue to past as you are still going to need support for a while.
There is nothing wrong w/deciding not to be a stander. You are the only one that can decide when you've had enough of the madness that is created by someone in crisis.
Letting go is very liberating and you will find that your focus will be more on yourself and what you require to be happy.
You are going to be just fine. One day at a time, one step at a time.
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.