If a person is angry with me, she is not wrong.
I may not think the anger is justified. But that has no bearing on whether it’s right for her to feel what she feels. Arguing that point is a losing battle.
A better alternative is to acknowledge her anger and discover the cause. Once you’re on the same side, then resolution suddenly becomes a lot more likely.
I’ve found this is a useful posture whenever I’m frustrated with someone’s perspective, belief, or state of mind.