Commentary on Meditations: B6:50

Try to persuade them, but act even if they are unpersuaded, whenever the principle of justice so directs. But if someone forcibly resists, change tack to an unhurt acceptance, so using the obstacle to bring forth a different virtue. And remember that you set out on a conditional course - you were not aiming at the impossible. So what were you aiming at? An impulse qualified by a condition. This you have achieved: what we proposed to ourselves has been accomplished.

Part of your duties, as a rational, social human being, is helping and teaching others.  Persuade as best you can.  But if they remain unchanged and unpersuaded, your duty is to not be offended or emotionally hurt. 

Rather, your duty is to pivot.  You pivot to another form of persuasion or you pivot to a different action or you pivot and begin to exercise virtue, such as patience.

Life is like Jazz and is not linear.  You may have a vision or an idea of how things will go.  You may plan to the n-th degree.  But in all this complexity, things are subject to change.  You don't freak out like a child who doesn't get candy when her mom says no to her while they are shopping.  Rather, you accept whatever happens and pivot.

(see also Citadel p. 198, 225, 228)