There may be a difference for you, subjectively. As others have pointed out in their answers, you would be telling people the truth about the narcissist, while the narcissistic smear campaign is a lot of lies and exaggerations, with possibly only the smallest kernel of truth at the bottom of all of it.
But, to outside viewers, it just looks like an epic (or petty) grudge-fight between two people who are putting dirty laundry out for all to see. No matter how right you are, and how wrong the narcissist abuser is, it’s just embarrassing and distasteful for others to see or hear about.
The only people who care about who did what to whom will either be drama-addicted ‘flying monkey’ type people (the narcissist’s enablers and audience members) or your own closest friends and family.
For anyone outside of your most trusted circle, you should not bother with ‘exposing’ the narc, because they either will not care, they will enjoy the gossip & pass it around, and/or they will think you are just as bad as the narc.
Fun bonus for attempts to expose the narc: negative publicity is still publicity, in the mind of the narcissist ‘star’ of the “Great And Wonderful ME! Show” They will enjoy knowing that they still take up so much of your time, thoughts, and energy. Your pain, aggravation, and attempts to expose them will just feed their ego and make them feel more and more powerful and superior.
The best way to win against one of these people is to ignore them. Act as if they do not exist. Don’t let them see that they’ve hurt you.
If their behavior has caused you harm, file charges.* Don’t talk about it with everyone, just take your information to law enforcement or a lawyer. Otherwise, just ignore petty gossip and go on about your life. Exposing the narc to mutual friends, social groups, and acquaintances is not going to give you the results you want, it’s just going to give the narc fuel and make you look crazy. (speaking from experience here!)
*Disclaimer: I am not a lawyer. Consult a lawyer specializing in 'high conflict' if you are looking to take legal action against a narcissist/abuser.
Editing to add: Posts tagged 'quora' were originally my answers to peoples' questions on quora.com. They were monetized but I am giving them away for free here.
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