No, really. Do it.
Think about how to do it best, of course, but go get angry, and go change the world.
There are lots and lots of cliches that people will tell you about anger. Some of them are true. Some are not. Go ahead and write while angry. Don't hit send, but go ahead and write that reply, go ahead and write that letter, go ahead and blog about it while you are still seeing red. Wait to publish or send until you're at least to a point of calm anger, so that you can check to make sure you didn't say anything that will just make it worse, but write while you are still angry. Use that anger.
Anger is some of the best fuel you will ever get, and it's free. All it takes to get is someone doing something to you that was wrong. Go. Being nonviolent doesn't mean you can't get angry. It means you can't go smack the person who angered you upside the face, but writing about exactly why it was wrong and how to fix it, even on the internet, is probably going to change more than hitting them anyways. Hitting them might get that one person to not mess with you again. Maybe. Or it might just get you in more trouble. Blogging about it has the chance of creating a social media crisis where they are willing to make whatever changes they have to to make it all just go away. Sending a letter has the chance of reaching a superior who had no clue this was going on and now wants it to stop. Making it an open letter that you send gets you both of these things.
Besides, one of the cliches that is true is the one about a small group of dedicated and concerned people being what changes the world. This small group may or may not have been nonviolent, but I would bet that anger was usually at least part of their fuel.
I can tell you that anger is often my fuel. With executive functioning issues, I'll take whatever fuel I can get, and anger works.
So go get angry and change the world!