I believe that the most important measure of success and maturity at my age is whether you’ve managed to shift the locus of control over your life inwards. This is almost impossible at 20 or 25. But at my age, it’s pretty crucial.
A small test of whether the locus of control is internal or external is to think back to the time recently when you had a really shitty day and ask why it was shitty. If the answer begins with, “it’s because I …” the locus is internal. The next question is, what happened to make things better? If the answer starts with “I did / said / decided, etc,” again, the locus of control is internal and you are on the right path.
Obviously, we don’t choose the bad shit that happens to us. And it happens to absolutely everybody pretty regularly. Every human being carries a list of real personal tragedies in his or her memory. But we are the story we weave out of these tragedies. I am the story I tell myself about the events in my life. Maturity arrives on the day when you realize that the author of story – if not of the events – is you.