A look at kids (or adults) and the effects of trauma points to something other than just so-called brainwashing.
Under some circumstances detecting betrayals may be counter-productive to survival.
Specifically, in cases where a victim is dependent on a caregiver, survival may require that she/he remain unaware of the betrayal. In the case of childhood sexual abuse, a child who is aware that her/his parent is being abusive may withdraw from the relationship (e.g., emotionally or in terms of proximity).
For a child who depends on a caregiver for basic survival, withdrawing may actually be at odds with ultimate survival goals, particularly when the caregiver responds to withdrawal by further reducing caregiving or increasing violence. In such cases, the child’s survival would be better ensured by being blind to the betrayal and isolating the knowledge of the event, thus remaining engaged with the caregiver.
Betrayal trauma occurs when the people or institutions we depend on for survival violate us in some way. An example of betrayal trauma is childhood physical, emotional, or sexual abuse.” from
…the core issue is betrayal — a betrayal of trust that produces conflict between external reality and a necessary system of social dependence.
…if the person who has betrayed us is someone we need to continue interacting with despite the betrayal, then it is not to our advantage to respond to the betrayal in the normal way. Instead we essentially need to ignore the betrayal.
Betrayal trauma theory
Plus a thorough examination of Loss of the Assumptive World,
A Theory of Traumatic Loss – the reconstruction of meaning processes, the nuanced relationships with self and others, the wide range of psychological processes and “what cannot be said” in response to traumatic loss. at Amazon