The Little Shaman is a spiritual coach & specialist in cluster B personality disorders, with a popular YouTube show and clients worldwide.
If you don't already know, flying monkeys are what we call the people the narcissist manipulates into doing their dirty work, usually recruiting them to attack someone they are smearing or otherwise abusing. The term comes from The Wizard of Oz. Remember the Wicked Witch sent her flying monkeys out to attack Dorothy and her friends? The witch didn't go herself, she sent her minions to do the heavy lifting. This is the dynamic we see between narcissists and flying monkeys. It's sometimes called "abuse by proxy," or "gangstalking."
Now, some flying monkeys are narcissistic themselves, or they might have a motive of their own. Maybe they don't like the target anyway, for their own reasons, and they are just looking for a reason to attack this person. Most flying monkeys are well-meaning though. They have been manipulated to believe the target is evil, and they believe they are defending the narcissist or the narcissist's family. People usually believe the narcissist's stories of evil and abuse, unfortunately, because why would somebody make that up? Often, this a person's sad first introduction to the mind of the narcissist, when they realize these things were not true and they've been manipulated into abusing someone who has done nothing wrong. Even more sadly, people often don't realize it until they themselves have become the target.
If you were a flying monkey, don't beat yourself up. Most decent people would be outraged upon hearing the lies the narcissist tells about their targets - and the narcissist knows that. That's why they do it. They know they're lying, and they're doing it because telling the truth would not get them what they want. They want to discredit their target so that no one will listen to them. That way, their secrets are safe. They want sympathy. They also want to make other people dislike this person because they now dislike this person.
As with many of their behaviors, this is really nothing more a childish play on the emotions of other people. In a very real way, this is no different from Little Suzy telling lies about Little Janie and spreading them all over school so that no one likes Little Janie anymore. That's a big reason the narcissist's lies are believed. If it were a child saying these things about another child, it would be looked at as just kids fussing with each other and dismissed. Because it is an adult saying it about another adult, it is taken seriously because what adult would make that up? No adult person is going to try to ruin someone else's life for no reason, right? Maybe get them put in jail, or get their kids taken away. So people believe them. You can't beat yourself up for that. It's a normal reaction. The narcissistic person who is telling the lies is the abnormal one. Just like with children, they have no real understanding of the damage they are causing, nor do they care.
When people realize they have been used in this way, they may be very angry but they may also feel guilty. This is normal too; any decent person would feel bad knowing they've hurt someone for no reason. You might decide to apologize to the person you hurt, and let them know that you now see the narcissist for what they are. They may or may not want to hear from you, of course. Depending on what has happened you might not be able to apologize. The person might have moved away or blocked you out of their life, or changed their number. Maybe you didn't really know them well enough to even be able to contact them. So how do you deal with the guilt?
You have to be honest with yourself about what you did and why you did it. This is the only way you can learn from the situation so you can forgive yourself and move on. Maybe the target was your narcissist's ex, and even though you believed their lies about the ex, you also found it easy to be abusive to this person because of jealousy. Maybe the target was a co-worker and though you believed the lies, you also found it easy to gang up on this person because you didn't really like them anyway. There is a reason you decided to jump in and fight someone else's battle on their behalf. Maybe it was a good reason and maybe it wasn't. The important thing is to understand it within yourself and to be totally honest with yourself about it. Understanding what you did and why you did it is the key to learning from experiences. Otherwise, we would all be like narcissists, walking through life simply reacting to things without ever even knowing why or how to stop it from happening. Unlike narcissists, most people can learn from experiences. They can take responsibility and they can forgive themselves. The lesson we so often learn from narcissists is that we should be cautious taking other people at their word, and cautious of our own emotional reactions.