You can't. Blood will always be thicker than water, and the picture the N paints to the world is only with their colors, not with reality. His family will be in denial and believe anything the N tells them about you. With a N, it's everyone else's fault - never theirs. They are cowards. They can't face themselves and who they are. Don't expect the impossible. They are spin doctors and weave tales to suit their needs at your expense.
The best you can hope for is to try to have his family question his core beliefs and values. Therein lies the truth. However, be prepared for the N to take you down in the process. Look how long it took you to figure it out. As much as you want the wolf in sheep's clothing exposed, what is your objective? Revenge? You may want to "expose" the real person, for the world to see how evil they are, since you have first hand experience, however, it will be your word against the N's. Don't waste your precisous energy on a coward. Your best revenge is to live well.
Not unless you are prepared for the backlash. Narcissists thrive on blame and are experts at twisting the truth to make themselves appear the victim. Most of those who have spent a significant amount of time with a narcissist will tell you that it is better to walk away than get even. Although it may hurt at times, try to remember that life is better when shared with someone who truly cares for you and vice versa. Pity the narcissist and know that they will never know true happiness.
Be very carful doing that because a narcissist can become dangerous. What you can do is don't give them their narcissistic supply and that hurts worst then exposing them.
Yes but do so anonymously.
Tell him to go and leave you alone.
Just because this person is a narcissist doesn't make then much different than anyone else cheating with your spouse and you should be more concerned about your spouse cheating. By all means sit down with the narcissists spouse and tell the whole story, but be sure you have absolute proof before doing so. Don't be surprised if the narcissist's spouse becomes angry and is denial, but, in time the spouse will become to believe it.
You should ignore them back and be thankful you are not in their circle of victims. Get on with your life and don't fret over not getting attention from a narcissist.
Yes. Otherwise they'll get deeper and deeper into it. At lease they have a fighting chance if you tell them.
Only if you are masochistic.
Of Course
You grieve for the relationship you SHOULD have had.
yes
A borderline. Essentially a more emotionally reactive narcissist.
Please NO!
It is bad and you should run fast and flee town.