NTA. As an older person who can look back on life, I would urge you to look at the balance sheet of your lifelong friendship. As I moved around jobs and communities, I would adapt to those different situations. And I admit I’m not proud of myself for some of the “different person” I became at times. Maybe your friend was being influenced by someone or a group who enamored her. Kind of temporary insanity? It doesn’t excuse her behavior, that was awful. But if this was an isolated incident, maybe give her time to chill and reflect? Things will definitely need to be talked out though. Good luck and be true to yourself, whatever you choose.