Its not that the mothers are unaware in these cases they are in a deep sense of denial and have been living in denial for many years sometimes decades.
Imagine a mother ignoring ever motherly instinct that her child is in danger and being abused. There is a great deal of complex emotions going on shame , powerlessness & guilt. In these case I think often the mother makes excuses and some how convinces her self that the child brought this on herself.
The same thing happens at these cults where the religous leader (crazy man) convinces everyone he is the messiah or whatever then the guys become his bodygaurds and all the girls become his concubines mothers and daughters under age and all.
I think in the end the child who suffured can recover alot better than most people think. As most assume they are going to be broken for life but if that where the case they could have commited suicide long ago. In the end I think once removed from the cycle of abuse they find a way to move on as they are truly the innocent victim in this.
Where as the mother will always have to live with the guilt she let this happen and didnt protect her child even when she had the chance to seek help plus now the whole world knows of her shame she is exposed.
We would all like to believe that any mother would jump thru fire to protect her child but thats simply not reality. Some mothers would risk thier lives and do anything to protect thier children. While others would abandon them to party the night away. Others simply lack courage to stand up for themselves let alone thier child.
I think this case is the latter as this woman was probably threatened and lacked the courage to stand up to intimidation. Its sounds like a simple thing but its not as talk is cheap....