New Level of Lying
I was at my daughter's school yesterday helping out. At lunch, one of the lunch monitor's came up and asked which kid I belonged to. I reached over and hugged my daughter. The lunch monitor looked at my daughter and said, "I thought you said you were in foster care." My daughter dipped her head.
It would seem that the tale around school is that she is in foster care now. Whether it is to get attention or to make people feel sorry for her so they won't pick on her, I'm not sure (the bully that has been bothering her came up to me and said that if she had known that my daughter was in foster care she never would have bugged her).
My daughter did apologize to me and gave me a hug later and we did discuss the situation (although the result was that somehow everyone "misunderstood").

Comments
Perhaps there is an element of her past blobbing up with the present? You did foster your DD for a period of time prior to adopting. Or perhaps it is related to the bullying. Or perhaps there is an element of fantasy that there will be other families for her in the future.