How do I tell my best friend that I don’t want to be friends anymore?

You need to be straight-forward with her. Tell her what you told us -- that she's more of a dictator than a friend and she's very rude to you. Try to do it in person and also (and I think this is important) do it as calmly and nicely as possible. If you come across as angry or like you're attacking her, she's not going to respond well. This way you can actually speak about the problem and possibly solve it. I recently lost my best friend because he decided that he didn't want to be mine anymore. I wish he had spoken to me -- even if it was just to end the friendship -- because there's nothing worse than treating someone like they're not a person. Good luck and I hope things end well!

I've experienced that before and it's true, you need to be straight-forward. People like that sometimes don't understand that they are hurting the person or just flat out don't care. In order for you to earn some respect, you need to set down the lines and tell her that she's stepping out of line. Friendships are like relationships and if you both don't pull equal weight, well it's pretty obvious it isn't a friendship anymore. Trust me, I've been through this and it's rough as hell and sometimes it may take you a few tries to pull it off, but in the end, if you guys weren't meant to be friends, you'll just go separate ways. You just need to trust yourself and learn to function without her, best friends are tight bonds that hurt when they are broken. That's why you need to learn how to function independently so you can stand on your own, without her in your life. Look, it's going to be rough, but your life will be a lot less burden-full.