I struggle with CPTSD and lived with a narcissist - I m free of him now and this is what helped me most - Narcissists are very good at pushing your buttons, often in a way that's subtle enough that no one but you would know it was intentional. And even when you call them on it, they gaslight you and tell you they "never said that", "were only kidding", or that you "took it too seriously." (overreacting or just plain didn't get it)
If the thing they say or do to bother you is blatantly cruel, they will make sure no one is around when it happens, and if you tell anyone about it they will deny it and claim you're crazy and making things up to cause problems. If they're able to poke at you in a more subtle way that only you would understand, they prefer to have an audience. This way, they can show everyone how "oversensitive" and "crazy" you are. In this way, the narcissist is able to abuse you, make you angry and frustrated, humiliate you, and confuse you into thinking YOU are the real problem. They know exactly what makes you tick, and they will do and say whatever they know will bother you the most and get the best reaction.(or go behind your back to mutual friends claiming they are the injured party)
Publicly embarrassing their targets is one of their favorite things to do. It's not only fun and entertaining for them, it's also a great way of shaming you into thinking there's something wrong with you for finding fault in their behavior.( one of my fears and a source of great anxiety) If you have an emotional outburst , you will most likely shift your attention off the narcissist's behavior and onto your own because of the embarrassment you feel. And because the narcissist is so great at gaslighting, twisting things around, and feigning innocence, you will be left confused and ashamed, convinced that there must be something terribly wrong with you. ( but I refuse to let you do this to me, I am busting you on this and so no more)They will sometimes even pretend to be sympathetic to your "problems", saying things like "I know you can't help it." and "It's just the way you are." This further enforces the illusion they try to make everyone believe, which is that there is nothing wrong with their behavior and that your "overreactions" are the real problem.