I added this post to my HN favorites.

I experienced myself at least two of those points. In different words:

Never teach to people that did not ask you to teach them. They will not listen to you. They will forget. They will not thank you. Time wasted. As a corollary, I'm sorry for most teachers at school and even at universities.

You can change your mental state. A friend of mine told me about 3 years ago "When X happens I can't change the way I react" and she was not necessarily reacting in a good way. My answer was "Your mental state is the only thing you can control." She stopped talking and started thinking. I don't know if it had an effect. Changing the way one reacts to a stimulus takes time and effort but it can be done.