It is not reasonings that are wanted now; for there are books stuffed full of stoical reasonings.

The argument has already been made, many times, better than you will make it. What is missing is never another explanation of why calm is preferable to panic; it is a person actually being calm at four in the afternoon when the thing goes wrong. Reading about a way of living is pleasant and feels like progress, which is precisely the trap. Understanding accumulates while conduct stays exactly where it was.

Close whatever you are reading on the subject and spend the week doing one small piece of it instead. Choose the situation you handle worst and handle it once the way the books describe, badly if necessary.