Life Choices

I always tell my kids life is about the choices you make and how you handle the choices others make for you. That you can't control others, only yourself. Its important they know to always take 100% responsibility for their part in their relationships with others so if something negative comes out of it they'll know they tried their best. I want them to learn this hard truth years before I did, I want to save them the trouble of learning how to take ownership. With any luck it will click with them before it did for me, though I recognize they are on their own path of self discovery and that inherently will mean a path uniquely theirs. However there are still times I find myself angry over someone else's choice. Angry enough that I just want to shake them. I know their experiences along their path to who they are today are different from my own, but non the less, angry I become. So how do you truly let go when you find yourself still angry? How do I practice what I preach?