How should I handle the situation with this girl?

you need to tell her the thing she does are RUDE. i have a friend like that, she doesn't mean to be rude but she doesn't realize shes doing it. let her know the things she does annoy you and you want her to act like her old self. try hanging out with her, with just the 2 of you and avoid situations like what happened with her dad. if shes still rude after that, then just ignore her after that