First filter
Nah, I'm not doing that private stuff. I don't know you and if you're filtering to this many people to bitch about it to start, then there's no need to drop under private filters to narrow the number of people who see you judging her more harshly. Share with the whole class.
That's because there isn't. It's taboo, but there's nothing wrong with her behavior beyond the fact that you don't like it. So how about you just don't read it? Seems like you both win, that way.