This seems a very difficult term, it came to my realization years ago when I read a nice book about “Dr. Jekyll & Mr Hyde” symptoms.
It opens my eyes and motivate me to learn more about this topic, which happens commonly among abusers / narcissists.
Many occasions, people shocked me when I found they act totally differently in public and behind doors. This make me feel more uncomfortable to deal with so-called charming person because I witness many lies behind.
How about you? have you ever meet this type of people?