People are filming their exes having narcissist meltdowns. A therapist explains what causes them.

• Narcissists throw tantrums when they feel caught in a lie or embarrassed.
• A therapist explained that these tantrums can manipulate partners into keeping quiet.
• More people are documenting their exes throwing fits as a way to highlight relationship abuse.

Dating a narcissist can start off really well — almost suspiciously so. Narcissists are known for behaviors such as love bombing, where they shower their partner with affection at the very beginning of a relationship.

But eventually, the mask slips off. And when you start arguing with a narcissist, you may find yourself witnessing a childlike tantrum that can involve yelling and even throwing things, Leah Aguirre, a licensed clinical social worker in San Diego, told Insider.

"It is kind of like you would see in a kid, someone who cannot regulate their emotions, who cannot react in a way that's appropriate for their age," Aguirre said. "They don't really have any self-awareness of how this looks, how this might be perceived by other people."

Increasingly, examples of these "narcissist tantrums" have been making the rounds on TikTok.

In a viral video that got over 20 million views, TikTok user @royalandwavey's fiancé was shown sitting fully clothed in the shower after he allegedly told her he got someone else pregnant.

Other videos have shown partners writhing on the ground or following their partners when they've been asked for space.

While narcissistic tantrums aren't new, Aguirre spoke to Insider about why these videos are making the rounds online.

Narcissists manipulate their partners through tantrums

Aguirre said that narcissists have tantrums when they feel cornered. Because narcissists thrive on having an inflated ego, "once someone calls them out or points out discrepancies between something they've said, that's usually when they'll tantrum," she said.

For the partner watching, it can feel like an impossible situation to be in.

"Oftentimes, people that are in any kind of relationship with a narcissist feel helpless," Aguirre said. "The only thing they can do is appease or agree," because the tantrum will often feel nonsensical and like an outsized reaction.

She said this can keep the partner in an abusive relationship, as they learn to walk on eggshells or avoid challenging the narcissist in order to keep the peace. Because narcissists often gaslight their partners and deny wrongdoing, the cycle can continue for years.

Most people throwing tantrums aren't true narcissists

True narcissism, however, is pretty rare. Aguirre said only a small percentage of people truly have narcissistic personality disorder (NPD) and that "it's impossible for everyone around us to be narcissistic."

True narcissism is comprised of other traits that an abuser might not necessarily have, like the need for excessive praise or extreme competitiveness.

Sometimes, she said people use "narcissism" to mean "emotionally immature," where some qualities can overlap with narcissism but the partner still has some empathy.

While she said that narcissism is a continuum and everyone can have some narcissistic qualities, diagnosing people with full-blown NPD can overlook other explanations.

For example, people with borderline personality disorder (BPD) can experience mood swings that resemble tantrums, but are caused by attachment issues.

"In general, a lot of personality disorders come from a lot of complex trauma and childhood abuse," Aguirre said.

While that doesn't mean a partner has a right to be abusive, more often than not, the causes for meltdowns and tantrums are "definitely more nuanced than just 'This person's evil or has no conscience,'" Aguirre said.

Younger people are more outspoken about abuse

Aguirre said that she's noticed that her younger, Gen Z clients "are less tolerant of manipulative, abusive, misogynistic behaviors."

So it shouldn't be a big surprise that these stories are proliferating on TikTok, where users are predominantly 18-34 years old. Aguirre said that spreading information online about how to spot an abusive relationship can be helpful — especially since about 41% of women and 26% of men will have experienced some form of stalking or physical violence from a romantic partner in their lifetimes.