Yes, it is unfortunate how often expressions of trust can be weaponized. Especially when circumstances call for one-sided openness and divulging of information, leading to vulnerability and some degree of temporary removal of personal boundaries.

We encourage our children not to mask their intelligence, to avoid dumbing themselves down in order to fit in or blend in or hide... and yet little eyes may see that their own parents may often have to set aside their knowledge and intellect while interacting with highly credentialed individuals asserting that their formal credentials are a proxy for superior knowledge in any particular topic, as well as an earned right to be first in SES pecking order.

This may happen any time there is a power imbalance... from educational advocacy to medical situations to justice system to counseling/therapy relationships. Unfortunately, for those credentialed individuals and the individuals they ostensibly serve, the concept of service may have fallen by the wayside.

These books came to mind, reading them may help others in similar circumstances to feel strong, recognize the dynamic of invalidation, and maintain a strong boundary between themself and anyone's attempts at invalidation:
1) Nasty People, how to stop being hurt by them without becoming one of them, by Jay Carter (1989)
2) Nasty People how to stop being hurt by them without stooping to their level, updated version, by Jay Carter (2003)
3) Nasty Women, by Jay Carter (2003)

He has also authored books on Nasty Men (2003), Nasty Bosses (2004), and co-authored a book on Bullies (1998).