Thanks for all of the great perspectives on this. I love this place; you're the only group that I can ask this of where the FIRST (and probably only) answer doesn't involve "how could you not think you were ruining your DD's life by accelerating her 3+ years...)

I think that this is some... thing... compounded by the drama associated with being a high-test variety of adolescent, hormonal girl.

She definitely seems uncomfortable and a little lonely when in a mixed-age group... as though she would LIKE to be accepted by the older kids, but knows better than to try to engage with them (her perspective, mind-- I've not personally SEEN much in the way of rejection there, just bewilderment occasionally).

It's as though she's responding to a perception of a no-win situation with typical adolescent over-reaction or something.

Schrödinger's cat walks into a bar. And doesn't.