I'm going to get into an argument with my gf's mom
I'm concerned about this. Why would you want to argue withh your girlfriend's mother?
She is a total bitch
Maybe you haven't gotten to know her very well. It's very rude to argue with your partner's parents. You may end up getting married one day and that would be a mess.
I'm going to tell her off and make it a big deal. I'm going to tweet it.
Is it fair for me to assume that you are just trying to get her provoked and not really making an effort to have a better relationship with your girlfriend's mother? I suggest that if you really dislike her, then you can just have a distance between you and her and just focus with your girlfriend if she's going to be okay with it.