I agree with Michelle. Just simply let her know you can't afford all that nonsense. Or you can just lie and say you broke your leg and can't make it lol. Okay I was kidding on that one
That sounds like an awful mess and she's being way too self indulgent. Not even bothering to think about how everyone else feels. Ugh, Bridezillas are awful aren't they?
Honestly, I refuse to be anyone's Bridesmaid. I would've politely declined her offer unless I'm able to choose the dress style that I want. I also wouldn't be happy about paying for it either. Those dresses are terribly overpriced in my opinion.
I think you should get yourself out of it. Dealing with all that isn't even worth it. Let her do her wedding thing on her own time and expense.