Americans are spending more time alone, marrying less, and making fewer friends than in previous decades. And it isn’t going well: A 2025 American Psychological Association survey found that around half of adults report feeling isolated, left out, or lacking companionship. Academic research suggests that around 37% of Americans suffer from moderate to severe loneliness.

For the past 25 years, I have studied what makes human life feel meaningful — and what happens when that sense of meaning erodes. My research on nostalgia, the bittersweet longing for the past, revealed something that surprised even me: the memories people return to most powerfully are almost never about personal achievement. They are about other people. Being cared for. Showing up for someone else. Belonging to something larger than themselves.

That work led me deeper into the psychology of loneliness, because the two phenomena are deeply intertwined. Loneliness is one of the most common triggers of nostalgia, and nostalgia reveals what true connection requires: conditions under which we matter to someone, and they to us. What I’ve learned is that Americans are not simply short on social opportunities. They are losing the conditions under which genuine human bonds form and hold.

Now some of the most powerful people in tech are offering a seductive solution. Meta CEO Mark Zuckerberg has argued that AI can help fulfill people’s unmet social needs. Many Americans are putting this idea to the test. According to a report published in Harvard Business Review, therapy and companionship is are now the number one use case for generative AI—up from number two the year before. The market is growing fast. Downloads and revenue are up sharply, and new AI companion apps are launching at a rapid pace.

I understand the appeal. AI is endlessly available, validating, and can produce a temporary feeling of being heard. But this approach fundamentally misunderstands human social nature. It treats social connection as a resource, something we receive when people are available, attentive, and kind. By that logic, a well-designed chatbot should do the trick. But a socially fulfilling life is as much about what we do for others as what they do for us. This is why people can feel lonely even when surrounded by others who are kind and supportive.

In my research, I’ve found that our social nature is ultimately existential, bound up with our need for meaning. Indeed, over 90% of Americans cite relationships as a key source of meaning in their lives. The memories people find most meaningful overwhelmingly center on interdependent relationships—the kinds of connections that require us to do things for others.

Critically, it is when we believe that we truly matter to others that we feel the most fulfilled. No matter how much AI can simulate social support, unlike real humans, chatbots don’t need us. They can’t make our lives matter.

There is also an agency component to meaningful social bonds. A chatbot doesn’t freely decide to show up for you. But when people do, it motivates you to do the same. Consider a story that has stayed with me. A reporter interviewed a mother at a free back-to-school event staffed entirely by volunteers from local churches. The supplies helped, she said. But what stayed with her was knowing that strangers had chosen to give their time for her family, which inspired her to want to do her part to make a positive difference in the lives of others. This made her feel like she mattered, and less alone.

Real social connections embed us in something larger than ourselves, connecting us to families, communities, organizations, and shared stories that provide us with transcendent meaning. This is the perception that even though we are mortal beings with limited time in this world, we play a significant role in an enduring cultural drama.

The experimental evidence backs this up. A new study found that first-year university students—a group naturally susceptible to loneliness—were randomly assigned to text daily with a custom-built AI chatbot, a fellow student, or simply journal for two weeks. The chatbot was specifically designed to embody the qualities of an ideal friend: active listening, emotional validation, empathetic responsiveness. The human texting partner was a randomly selected stranger, not an existing friend.

Despite all of that, only participants who texted with a real human peer showed a significant reduction in loneliness. Those who interacted with the chatbot reported loneliness levels statistically indistinguishable from those who simply journaled. Other research tracking longer-term effects has found that when people use AI for companionship, they eventually end up feeling more isolated.

AI can be a powerful force for human progress. But it cannot be a substitute for human belonging. Our deepest social needs aren’t about having support available on demand — they’re about mattering to the people who matter to us. The more we outsource that need to machines, the further we drift from the only thing that can actually fulfill it.

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