There's often far more to disturbingly "inappropriate" or "bad" behavior than immorality or poor parenting. Significant trauma enters the equation much more often than we think. "Knowing the difference between right & wrong" and "trying one's best" have very little influence when a posttraumatic reaction is triggered.
We may suspect, but usually have no idea about peoples' past history, even of those we've known for a long time. Trauma is not something most of us want to revisit, much less share with others.
“Paradoxically, the more we try to change ourselves, the more we prevent change from occurring. On the other hand, the more we allow ourselves to fully experience who we are, the greater the possibility of change."
Laurence Heller, Aline LaPierre. "Healing Developmental Trauma: How Early Trauma Affects Self-Regulation, Self-Image, and the Capacity for Relationship.” North Atlantic Books, 2012.
“…trauma is much more than a story about something that happened long ago. The emotions and physical sensations that were imprinted during the trauma are experienced not as memories but as disruptive physical reactions in the present.
… the engines of posttraumatic reactions are located in the emotional brain. In contrast with the rational brain, which expresses itself in thoughts, the emotional brain manifests itself in physical reactions: gut-wrenching sensations, heart pounding, breathing becoming fast and shallow, feelings of heartbreak, speaking with an uptight and reedy voice, and the characteristic body movements that signify collapse, rigidity, rage, or defensiveness.
…the rational brain cannot abolish emotions, sensations, or thoughts (such as living with a low-level sense of threat or feeling that you are fundamentally a terrible person, even though you rationally know that you are not to blame for having been raped). Understanding why you feel a certain way does not change how you feel. But it can keep you from surrendering to intense reactions (for example, assaulting a boss who reminds you of a perpetrator, breaking up with a lover at your first disagreement, or jumping into the arms of a stranger.) However, the more frazzled we are, the more our rational brains take a backseat to our emotions.
The fundamental issue in resolving traumatic stress is to restore the proper balance between the rational and the emotional brains, so that you can feel in charge of how you respond and how you conduct your life. …
Recovery from trauma involves the restoration of executive functioning and, with it, self-confidence and the capacity for playfulness and creativity.
If we want to change posttraumatic reactions, we have to access the emotional brain and do ‘limbic system therapy’: repairing faulty alarm systems and restoring the emotional brain to its ordinary job of being a quiet background presence that takes care of the housekeeping of the body, ensuring that you eat, sleep, connect with intimate partners, protect your children, and defend against danger.
The neuroscientist Joseph LeDoux and his colleagues have shown that the only way we can consciously access the emotional brain is through self-awareness, ie by activating the medial prefrontal cortex, the part of the brain that notices what is going on inside us and thus allows us to feel what we’re feeling. (The technical term for this is ‘interoception’ – Latin for ‘looking inside.’) Most of our conscious brain is dedicated to focusing on the outside world: getting along with others and making plans for the future. However, that does not help us manage ourselves. Neuroscience research shows that the only way we can change the way we feel is by becoming aware of our inner experience and learning to befriend what is going on inside ourselves.”
Bessel Van Der Kolk. “The Body Keeps the Score. Brain, Mind, and Body in the Healing of Trauma.” Penguin Books, 2015.