So apparently a couple weeks before BMs random flip out where she declared SD couldn't come here anymore, her and SD had been fighting so badly that she enlisted GBM to talk to SD. GBM tried to have a discussion with SD about open communication with her mom and being nice to her and not telling BM that she doesn't care about things. SD said she didn't want to discuss anything at all with either of them. Another time SD apparently just randomly hung up the phone on GBM. Also, SD said its her fault she's late for school because she refuses to get up in the morning and her mom gets upset about it and rushes her.

So first of all, I was correct in that her attitude is the same at BMs as what I typically see. But beyond that- the fighting and not listening to BM must tie in somehow to BMs flipping out on us and saying SD can't come here anymore? And then going to the school counselor and blaming DH for SDs behavioral issues? Was she opening DH would flip out and demand to have SD fulltime? Was she just scapegoating DH? 

Also, BM is going to meet up with some guy she met online that lives on the east coast (we're in the Midwest). So I'm sure that explains at least part of why she doesn't want to be locked down into full custody permanently.