For me, it's a question of deception. Rachel was not forthright about her background. She deceived an already vulnerable community and took a position of leadership under false pretenses.
She could have been a great ally and activist, but she chose instead to be dishonest.
I would say Rachel is certainly damaged from a abusive childhood and there's an obvious need for her to distance herself from her family in every possible way. However, it doesnt excuse her behavior. She also seems unable to stop seeking attention for herself, even at the expense of her own children, who are begging her to stop outing the family.
It's truly sad because she obviously loves her children and her adopted siblings, but her trauma and the way it's twisted her perception has warped her judgement.
That being said, this is bigger than one person. Her lies further damaged an already fraught relationship between races.