Think about your closest friend from ten years ago. Are you still close? If not, you probably didn't have a dramatic falling out. More likely, life just... happened. Jobs changed, someone moved, kids arrived. The friendship didn't end—it slowly became too expensive to maintain.

We rarely think of friendships in economic terms, but they operate on surprisingly similar principles. Every relationship requires investment: time you could spend elsewhere, energy you could direct toward other goals, sometimes actual money for meals, trips, or gifts. Understanding these hidden costs helps explain why our social circles shrink and shift in predictable ways—and why maintaining meaningful connections feels harder than it used to.

Every friendship has a maintenance budget, whether you realize it or not. There's the time you spend together or communicating—texts, calls, planning hangouts. There's emotional energy—remembering what's happening in someone's life, caring about their struggles, celebrating their wins. And there's often literal money: splitting dinner tabs, buying birthday presents, traveling to weddings.

These costs aren't bad—they're the substance of connection. But they're real, and they compete with other demands. You have roughly sixteen waking hours each day. Spending two hours catching up with a friend means two fewer hours for work, family, exercise, or rest. Your attention is genuinely scarce, and every relationship claims some portion of it.

The tricky part is that maintenance costs aren't optional. Friendships aren't like savings accounts that quietly hold value while you ignore them. They're more like gardens that need regular tending. Skip the watering long enough, and you return to find weeds. The sociologist Robin Dunbar famously estimated we can maintain about 150 meaningful relationships, but even that requires constant cycling of attention. Your five closest friends might need weekly contact; your next fifteen need monthly. The math gets demanding fast.

Takeaway

Friendships aren't free—they draw from the same limited pool of time and energy as everything else in your life. Recognizing this isn't cynical; it's the first step toward investing intentionally.

Here's a pattern most people recognize but rarely examine: your friend group probably looks very different than it did five years ago. This isn't random drift. It's structural reorganization driven by changing resource availability and alignment.

Major life transitions—marriage, parenthood, career changes, relocation—dramatically alter your resource budget. New parents don't stop valuing friendship; they suddenly have far fewer hours and less energy available for any relationship outside their immediate household. Meanwhile, their priorities shift. They now need friends who understand interrupted conversations, who can meet at parks rather than bars, whose schedules accommodate early bedtimes.

This creates what sociologists call homophily pressure—we're drawn toward people in similar circumstances because the maintenance costs drop dramatically. Two parents can combine socializing with childcare. Two professionals in the same industry can network while catching up. The friendship feels easier because the resource exchange becomes more efficient. This explains why life transitions so often trigger friend group reshuffling. It's not that people become shallow. It's that the economics of connection suddenly favor different relationships.

Takeaway

When friendships fade after major life changes, it's usually not about affection—it's about misaligned resource budgets making the maintenance costs suddenly much higher.

If friendships require investment, the obvious question is: how do you build relationships that survive resource constraints? The answer isn't simply 'try harder'—it's designing for sustainability from the start.

Low-maintenance rituals create connection without demanding constant attention. A monthly phone call with a college friend. An annual trip with a small group. A group chat that doesn't require immediate responses. These structures reduce coordination costs while preserving the relationship. They acknowledge that everyone's resources fluctuate while creating reliable touchpoints.

Diversified portfolios also matter. Relying on one or two relationships for all your social needs creates fragility. When one friend becomes unavailable—new job, new baby, new city—you're suddenly isolated. Building connections across different contexts (work friends, hobby friends, neighborhood friends) spreads the risk and ensures that life changes don't eliminate your entire support network. Finally, some friendships simply become dormant rather than dead. Recognizing the difference helps you avoid guilt about relationships that are merely hibernating, waiting for circumstances to realign.

Takeaway

Sustainable friendships aren't about maximum intensity—they're about designing low-friction ways to stay connected when life inevitably gets complicated.

None of this means friendships are cold transactions. The economic lens simply makes visible what's always been true: relationships require resources, and our resources are finite. Understanding this helps explain painful patterns—why closeness fades, why life transitions reshuffle our social worlds, why maintaining friendships feels harder in busy seasons.

The good news is that awareness creates agency. You can invest more intentionally, design for sustainability, and stop blaming yourself or others for natural structural pressures. Friendships are worth the cost—but only if you're honest about what you're paying.