Narcissism and Infidelity: An Insatiable Quest for Validation and Adoration

This week's Fidelity Factor is a big one, because the overlap between narcissism and affairs is high. Not all affairs are had by narcissists—but almost all narcissists will have an affair, multiple affairs, or engage in some kind of betrayal over the course of a relationship. In my line of work, it's absolutely essential to know if someone is married to, or is, a narcissist, because of the way this personality style impacts the ability to productively move forward.

In short, narcissists do not change. They can get on better behavior in the short term to get the outcome they want, they may soften, they may become vulnerable, but over the long term they will not change. This matters hugely when I'm helping a couple or individual who is hoping to heal from infidelity. More on this below, under "What to Do About It."

Narcissism can play a powerful—and often destructive—role when it comes to fidelity. At its core, narcissism is marked by a deep and insatiable hunger for admiration and validation. For someone with narcissistic traits, the steady rhythm of a long-term relationship may feel like it no longer satisfies this need. Instead, they may begin seeking attention outside the relationship—chasing the high that comes from being desired, admired, and seen as special by someone new. We think of narcissism as grandiose, but the truth is, it takes on MANY different shades and tones, and exists on a spectrum. This is an extremely tricky personality style indeed.

Let's take the example of the pregnant wife. Her physical abilities are being hampered, she's tired, and life is about to change. For her narcissistic husband, his instinct is to begin to feel a growing resentment and dissatisfaction in the marriage.... and with his spouse. The baby arrives, and at home, life feels mundane—full of routines, responsibilities, and emotional demands he doesn’t really want to meet. He puts on a good enough show, but he's not truly "there." His wife feels at times like a single mother, but she's so wrapped up in the baby and postpartum recovery that she pushes her feelings down and away.

Meanwhile, at work, her husband starts flirting with a co-worker. This new person laughs at his jokes, compliments his ideas, and makes him feel like the smartest man in the room. That attention becomes a mirror reflecting back the image he wants to see: confident, successful, wanted. It’s intoxicating.

As the husband steps into an affair, his underlying thought process is a wounded one. He thinks: "I deserve this. If my partner truly loved me, I wouldn’t have to look elsewhere.” This kind of thinking not only minimizes the harm being done but often flips the script—making the narcissist feel like the victim instead of the one who is breaking trust. The emotional fallout on the betrayed partner is rarely acknowledged, because a lack of empathy is another hallmark of narcissism.

Affairs can also serve as an escape hatch. Vulnerability—true emotional intimacy—requires honesty, humility, and emotional presence, which can feel threatening to someone whose identity is built on being admired, not truly known. So instead of facing uncomfortable truths or repairing a strained connection, they may opt out emotionally, turning to an affair to maintain a sense of control and emotional distance. The narcissistic partner isn't going to truly lean into a relationship, because they're not willing to change, and they know it. Be forewarned: Instead, they expect their partner to change.

What To Do About It

I'm a therapist, and our outlook as clinicians is that people can always change and grow. Unfortunately, not someone who, overtly or covertly, displays a narcissistic personality style. Their awareness is too limited, their ego too fragile at the end of the day, and their psychological development arrested in a way that truly changes the way they function in the world and in relationships. This personality style prevents the ability for real change the way most therapists, or partners, would hope to see.

Knowing this is the most important part of the battle. Because I've seen too many spouses spin their wheels trying to get their narcissistic partner to change, to recommit, to choose them, to show up the way they wish.... only to lose their sanity, health, and their life energy in the meantime.

The most important thing you can do, no matter what your role in the situation (you could be a betrayed spouse, an unfaithful spouse, or an affair partner and be dealing with a narcissist), is to educate yourself deeply about narcissism. Knowing the beast you are trying to tame is essential to caring for yourself in the short and long term. Should I Stay or Should I Go? Surviving A Relationship with a Narcissist is hands-down the most thorough and comprehensive book on how narcissism shows up in relationships, its impact, what to do if you're going to stay, and what to do if you're going to leave.

There is no way I could cover every important aspect of the overlap between narcissistic personality and infidelity, but I hope this week I emphasized just how important it is to educate yourself about it. You may be dealing with a grandiose narcissist, a vulnerable narcissist (sometimes referred to as covert), a malignant narcissist, or a combination. Whatever the type, if you don't identify it, you'll be a psychological mess before it's too late. Since no narcissist shows up on bad behavior all the time, and they can be truly charming, it's solidly confusing, and you don't know whether you're dealing with the devil or an angel.

Education is the first step. Having the courage to keep learning even when what you hear is uncomfortable or scary is the key. I believe in you! And remember that if you need help because of an affair, we're here for you. Explore self-help resources that are expertly designed to help unfaithful spouses, affair partners, and betrayed spouses move forward, or schedule a confidential session.

Lauren LaRusso, LPC, LMHC // Founder + Coach