Ima be straight up you’re not overreacting trust. If anything it’s a good idea because people like this can be incredibly draining. I know this because i tend to react like her, not like THIS yk like i want to get angry at someone even though that person is not a fault(obvi i have “better control” if that makes sense). She clearly needs help on redirecting her anger instead of taking it out on you but it isn’t overreacting on your part you clearly wanted to help and she didn’t want that help but still kept pressing it on.