It looks like she has the one really bad toe, and the tips of most of her toes may fall off as well. Most times with frostbite, the toes will eventually fall off on their own. It can take weeks. Any tips that are black will most likely come off with the toenail. Spray them with betadine or iodine. Once or twice a day. I think she may be fine once she recovers. This can happen if they get their toes wet in the freezing weather. I hope she does okay.