Staci i am in agreement with the other's i would confront her on this, but in a very nice tactful way, for example, i might say are you afraid of Keegan,?or you seem a bit uneasy around Keegan, is there a reason for that, you seemed ok with her before, has something happened to scare you? anyhow along those lines, i know you will find the right words to say when the time comes, but hey if it is really bothering you, say something and clear the air.,there might well be a simple explanation.

I would not judge her too harshly,there may well be some reason, and it might not be that she was sucking up in the beginning,you will never know unless you ask eh?