Some tips from someone who has dealt with a few classic narcissists: don't argue with them. They do not reason the way you do. One-word answers are best. Pretend you are a very dull, boring person with no opinions when you are talking to them. Never raise your voice or get angry. They will try to use the silent treatment on you: ignore it. But it works very well on them too. They will never, in a million years, apologize. But if they apologize, they are only trying to manipulate you further because their fear of abandonment has been triggered by your body language and tone. Always remember they lie constantly. They don't know what the truth is anymore.

These are strategies and perspectives I've learned from having narcissistic family members. I hope it helps. The best thing you can do is just not deal with them at all, but sometimes it's unavoidable.