Best friends

So I’m really afraid I’m losing my best friend. Things are distant lately and she’s been acting in disrespectful ways I’ve never seen her act in before. She’s going through some stuff right now, but I don’t find that to excuse the way she’s been treating me. She is supposed to be my maid of honor in October and I don’t know what to say or do to either fix the situation or end the friendship and move on. I am not okay with being someone’s punching bag.