The rest of us wouldn't be able to live with ourselves if we behaved in such a treacherous manner. However, a morally disordered narcopath does not have these same restraints. She has likely behaved this way before, and will probably do so again. Malignant personalities have major trouble maintaining healthy relationships, so they will be on the prowl for a new target as soon as they finish with you. (This means they have successfully driven you from your job or from your social circle. If you have young children, they also punish them by separating them from their friends.)
Even though a narcissist doesn't have a well-developed conscience, she knows that you do. That's why she'll try to play on your guilt, in order to make you feel as if you're to blame for all the problems. Somewhere in their development, narcissists learn how to read other people's emotions, in order to mimic the correct response when they need to do so. Because they've acquired this "skill," they are very good at anticipating how normal people feel and how we tend react. So she knows just the right buttons to push, in order to make you feel guilty and ashamed.
So, if you have a female malignant narcissist in your life, the best way to deal with her is from a distance. If she's a friend, cutting her out of your life will restore your peace. If she's a coworker, and you're a target, you might have to think about working somewhere else. If this is not possible, I suggest learning all you can about this disorder, so you can protect yourself from a dangerous person, not guided by a well-formed conscience.
Pixabay photo top by johnhain