There's one way to protect yourself from a narcissist. And it's surprisingly simple.

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When psychologist Lara Crowe asked a diagnosed narcissist one simple question during her research, his response revealed a surprising 'weakness' in the narcissistic mind.

The question seemed straightforward enough: "What hits harder — being ignored or blocked?"

He paused, and Crowe watched an internal struggle play out across his face. Even admitting weakness was a challenge for him, Crowe observed.

His answer stunned her.

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"Ignoring? That's not scary. Ignoring is opportunity," he said in a voice Crowe described as steady and calculated.

"It means the victim is still in the game. Ignoring lets me build new strategies, manipulate, find loopholes to hook them again. Ignoring doesn't touch my ego — it's just another game."

But Crowe's conversation, which she has since shared on Instagram, revealed something far more interesting in the narcissistic psyche — and exactly what strikes at the heart of their deepest vulnerability.

What is a narcissist's greatest weakness?

Crowe described a distinct change in his voice, a vulnerability creeping in where cold confidence had been just moments before.

"But full blocking..." he said, trailing off.

Crowe said that as the pause streched on, it was as if the word itself had physically struck him. When he continued, she described his 'mask' as slipping entirely.

"Blocking is different. It means I lost control. The victim left, erased my leverage, refused to play. It hits the ego because it makes me think, 'What's wrong with me? Why did I lose them?'" Crowe recalled him saying.

For someone whose entire identity revolves around control and manipulation, being completely cut off represents the ultimate defeat. It's not just rejection — it's erasure. And for a narcissist, being erased from someone's life is perhaps the most devastating blow of all.

Why narcissists thrive on conflict and fear blocking.

Speaking to Mamamia, therapist Jacqui Manning explained that narcissists have a twisted relationship with attention that makes blocking devastating to them.

"Narcissists have an insatiable need for attention, and conflict keeps the attention on them; [it's] the spotlight that they crave," Manning said. "They go by the credo 'any attention is good attention.'

"Conflict also fuels their appetite for power and control. They are often smart people [who] enjoy dominating others through manipulation, or wearing others down and 'winning' the arguments. In truth, they are causing chaos and confusion, and wearing their partner down."

That conflict serves also another manipulative purpose.

"Conflict can also allow a narcissist to deflect the problem away from their own shortcomings," Manning explained. "They are experts at making the other person feel like everything is the other person's fault, which can be a crazy-making experience for their partners."

So why does blocking hit them so hard? Manning said that it strikes at their core need.

"Blocking takes away their power, which they need to get what they want and for their own self-worth and validation. It cuts off their supply to the energy of others, which they suck dry to build themselves up," she said.

How to protect yourself through blocking.

For those looking to cut contact, Manning offered practical advice.

Complete blocking: "Block them on every channel: social media (make sure they're blocked in every way), email, phone, WhatsApp," she advised.

Seek support: "If you've been with a narcissist, it's likely that you'll feel like you've been in a daze from being gaslit often, so seek out support, ideally from a professional, but friends and family can help too.

"Be honest with others about your experiences. Don't have any shame or embarrassment — that should sit with the narcissist. This will take some unpacking and processing, and you shouldn't go it alone."

Stay grounded in reality: "Reflect on the reality [of the situation]; don't romanticise. Narcissists are often very charming and alluring and our brains can sometimes focus on the 'good bits' — don't do this. Write lists of the ways you were hurt and remember that is why you won't be tempted back."

When you can't completely cut contact.

For those who must maintain some contact for practical reasons like co-parenting, Manning suggested:

Practise 'grey rocking': "This is essentially where you act like a rock, giving out no or little information, feelings, reactions and let their performance wash around you, not taking any of it in. It can be a buffer to help you get the energy and strength to do what you ultimately should, which is leave or have as little contact as possible."

Communicate strategically: Manning recommended "communicating in writing or through co-parenting apps such as AppClose (court-preferred)."

She also advised: "If you have to meet up in person, and you feel uncomfortable, take someone with you or have them wait nearby."

The narcissist's confession reveals a crucial truth — your silence and absence are more powerful than any argument or confrontation ever could be.

Sometimes the strongest response is no response at all. Your power lies in not giving them the reaction they crave, so use it.

Feature Image: Getty.

You can hear more from 'The Friendly Psychologist' Jacqui Manning on Instagram or reach out on her website.