Is it rude to bash your best friend's bias?

[freya]

I mean, it depends on what you guys agree upon. If it bothers you, let her know straight up instead of asking us. If this person doesn't respect your wishes to not be bombarded with hate when you mention his name, they're not very considerate and maybe it's something to consider vis a vis your friendship.

Your friend could just be thinking she's joking around so it's fine. Some people don't know when they've taken it too far. You could try hurting her back but that would ruin the relationship but it seems you don't want that. Tell her you don't like it and go from there imo. 

[freya]

1 hour ago, xo Nix xo said:

I've let her know a couple times. She just goes "it's just a bias, why are you getting so defensive?" The reason why I asked is because I was feeling stupid for even getting upset and wanted to know if there was any validity in that.

People's feelings are valid. Yours are valid even if others think its stupid. You're not asking for much at all. You just don't want to hear bad things about who you like and that's fine. Tell her it doesn't matter if its just a bias, it's the equivalent of someone bashing your hobbies. No one likes that.

If she can't see your perspective, she's in the wrong.