There is a passage from Marcus Aurelius where he talks about sitting next to a smelly, rude person. We’ve all been there: stuck on an airplane next to someone who is crowding in your space, ignoring the basic rules of human etiquette or decency.

Our reaction? We stew. We think that staring daggers at them will do something about the situation. We compose a letter in our head to the airline. We text a friend to complain. We tell ourselves this is a way of coping, but is it really? Because we’re just getting angrier the more we think.

Marcus’s advice is basically this: Either say something (nicely) or let it go. Those are the only two options within your control. What you shouldn’t do is make yourself miserable while you hope the situation magically resolves itself. It won’t.

It’s a good reminder for most situations. Either take a proactive step to resolve the situation–even if that means being a little bit uncomfortable or confrontational–or stop thinking about it and move on. Everything else is a waste.