We know she has lied, and it just could be that she's a sociopathic liar.

There are other stories coming out, and we can't be sure of the truth of them, however here are some of them.

Her parents adopt black kids and raise them as fundamentalist Christians.
Her parents blanket trained their babies
They teach creationism and other fundamentalist christian indoctrination as part of their homeschooling
They may have physically abused their children (the younger step brother Rachael pretends is her son, sued the parents for emancipation because of this abuse and Rachael was given guardianship).
Her younger sister was sexually abused by her older brother. And there is a current legal case where both Rachael and her younger sister are accusing the older brother of molestation and sexual abuse.

If these stories are true, then I can easily imagine that Rachael hates her parents and white older brother and that she stood up to protect her younger adopted black siblings.

I can also imagine that she is damaged and felt it easier and more comforting to refuse to identify with her white family, and instead identify with her siblings. This might explain why she went on to study so much about African culture.

So those stories mostly come from Gawker.