I can see being scatterbrained, I get a bit like that myself. Still doesn't make it okay though. You were really hurt by this. The least she could do is respond to you when you told her how hurt you were by her ignoring you. I repeat: if she is angry and confused it is her problem. And if she does it a lot it's about time she learned that continuing with that kind of behavior is a good way to wind up with no friends.