This is why you should never object to a toxic fiance(e) even on pain of death:
"This is going to sound a little retro, but it's actually just practical advice: If you're a confident, outspoken woman, people are going to dislike you before you even open your mouth. Maybe you're a little harsh and a little obnoxious and a little offensive, like I am. Or maybe you're just too unbearably sure of yourself. Either way, you're a little quieter than usual, and they're still suspicious. Now imagine how much they'll hate you once you start speaking. I'm not saying never speak. I'm just saying, recognize the lay of the land, and be aware that if anyone's going to get scapegoated for something, it's you.
Now I want you, Driving Miss Dainty, to picture yourself saying something to your friend about his girlfriend. I want you to picture yourself rallying the group to stand up against her. I want you to imagine yourself spurring your boyfriend to action, and having him say to his friend, "You know, (your name here) is really the one who notices this stuff. She just thinks your lady is awful. She wouldn't leave me alone until I said something." Then picture your friend, who's pretty goddamn weak and also very attached to his fiancée and has probably been coached to tell her EVERYTHING ABSOLUTELY EVERYTHING THAT ANYONE EVER SAYS ABOUT HER, EVER tells his lady this tidbit, and now you basically have an evil queen with a magic mirror and a loyal huntsman, waging an all-out war against you.
Do you know what that's like? Let me break it down for you: You will be the identified problem. Not your boyfriend. Not the 53,000 other people who dislike this woman. Just you. You will be asked to eat shit, apologize, etc, and there she'll be, your evil queen—absurd, comically imperious—serving it up. And then, out of the blue, you're OUT—banned from all social settings. And when the evil queen and the remaining friends get together for fancy crab dinners at overpriced restaurants, they will agree, resoundingly, that YOU ARE THE BAD SEED. Not the one with the faintly purple skin and the evil red lips, cackling, and the long pointy black gloves, gesturing demonically. No. You."