Expect your child to mess up — all children do. And don’t get so upset when they mess up, when they don’t do what they’re “supposed” to do … because they’re supposed to mess up.
Expect your partner to be less than perfect.
Expect your friend to not show up sometimes or be irritating late.
Expect things to go not according to plan because most things do not.
Expect people to be rude sometimes because a great deal of them are.
Expect coworkers not to come through sometimes more than usual.
Expect teenagers not to wash their dishes or pick up their clothes, sometimes because most teenagers do not.
Expect the glass to break.
And accept it.
You won’t change these inevitable facts — they will happen, eventually. And if you expect it to happen — even see it as already happening, before it happens — you won’t get so upset.
You won’t overreact. You’ll respond appropriately, but not overreact. You can talk to the person about their behavior, and ask them kindly to consider your feelings when they do this … but you won’t get overly emotional and blow things out of proportion.