How do I trust someone again after being lied to?

You don’t trust someone new by deciding to. You let trust build out of small things they say and then actually do, while you keep checking whether your caution is about them or about the last person. One lie from one person is real information about that person. It isn’t a forecast for everyone you’ll date next.

Why does one liar make everyone look suspicious?

Picture Noor, 24. Her ex of two years told her he’d stopped talking to a coworker. He hadn’t. She found out from a screenshot a friend sent her, eight months after he’d sworn it was over. Now she’s on a third date with someone who says he’s “bad at texting during the week,” and her brain is already running the math on what that really means.

That reaction makes sense once you see what a lie actually breaks. In a classic 1985 paper, psychologists John Rempel, John Holmes and Mark Zanna described trust in close relationships as having three parts. Predictability: can I anticipate what this person will do? Dependability: are they someone I can count on when it matters? Faith: do I feel confident about where this is going, even without proof?1 A lie damages all three, but it hits faith hardest, because faith was the part you weren’t checking.

There’s lab evidence that deception is its own kind of damage. In experiments at the Wharton School, Maurice Schweitzer, John Hershey and Eric Bradlow had people play a money game with a partner who behaved badly. When the bad behavior came without a lie, a steady run of trustworthy actions restored trust. When it came with a lie, trust never fully recovered, even after a promise, an apology and consistently good behavior afterward.2 Those were strangers in a game, not exes. But it matches how being lied to often feels: it doesn’t just lower your trust in one person, it makes trusting at all feel naive.

Is everyone just lying, though?

Mostly, no. In a 2010 survey of 1,000 U.S. adults, communication researchers Kim Serota, Timothy Levine and Franklin Boster found that 60% reported telling no lies at all in the previous 24 hours, and almost half of all the lies reported came from just 5% of people.3 Self-reports have obvious limits, since people may not admit every lie. Still, the pattern points somewhere useful: a lot of lying comes from a smaller group of people, not evenly from everyone you might meet.

The apps add their own wrinkle. In a study of 80 online daters, Catalina Toma, Jeffrey Hancock and Nicole Ellison measured people’s actual height, weight and age and compared them with their profiles. Small stretches were everywhere, but they were small: in most cases about half an inch of height or five to ten pounds of weight.4 That’s worth holding onto. A little profile polish is common and annoying. It is not the same thing as the kind of lie your ex told, and treating them as equal will wear you out before you ever get to know anyone.

How do you tell caution from carrying it?

It helps to pull apart four things that usually arrive tangled together. Take Noor’s date:

• What happened: he said he’s bad at texting during the week. Then he replied Tuesday night with a long, funny message.
• The reading: he’s hiding something on weeknights.
• The fear: I’m going to miss it again, like last time.
• The next step: keep seeing whether what he says and what he does match.

Only the first one is a fact. The reading was borrowed from the ex. The fear is real and deserves care, but it’s about Noor’s history, not this man’s behavior. The next step is the only part she can actually act on.

A quick test: if a friend described this exact detail about someone she’d just started seeing, would you call it suspicious, or would you call it a Tuesday? Healthy caution looks at this person’s behavior over time. Carried caution looks at the last person’s behavior and projects it onto whoever is sitting across from you.

Can a new relationship actually undo this?

It can help, slowly. In a 2018 review, Ximena Arriaga, Madoka Kumashiro, Jeffry Simpson and Nickola Overall laid out a model of how romantic relationships can make people more secure over time. One idea from it: anxious insecurity tends to ease in situations that build your own confidence, while avoidant insecurity tends to ease through good experiences of actually depending on someone.5 It’s a model drawn from existing research, not a guarantee. But it fits the bigger picture. Trust doesn’t come back from a pep talk. It comes back from repeated, ordinary experiences of someone being who they said they’d be.

That’s predictability and dependability, rebuilt one small proof at a time. Faith comes last. That’s not a flaw in you. It’s the order trust usually takes.

What should you do this week?

• Say what happened, in one sentence, to yourself. “He lied about the coworker for eight months.” Not “everyone lies” and not “I’m an idiot for believing him.” Precision shrinks the fear.
• Choose small, low-stakes checks. Did they show up when they said? Does the story about their job sound the same on date three as on date one? You’re noticing, not investigating.
• Tell, don’t interrogate. You don’t owe anyone the full story on date two, but one honest sentence about why you’re careful can prevent a lot of misreading on both sides.
• Catch yourself testing. Going quiet to see if they chase, or asking questions you already know the answer to, makes a new person pay a debt they don’t owe.
• Let the lie belong to the liar. Someone who lied to you showed you something about themselves. It isn’t proof that your judgment is broken.

If the fear doesn’t ease, keeps you up at night, or has you avoiding dating altogether for months, a licensed mental-health professional is the right kind of help. Being lied to by someone close can hit hard, and you don’t have to sort it out alone.

What doesn’t the research show?

• The Wharton experiments used a money game with strangers,2 so they show how deception affects trust in a lab, not how it plays out between exes or new partners.
• The lying survey relies on self-reports,3 and people may undercount their own lies.
• The online dating study checked height, weight and age,4 not lies about feelings, other partners or intentions.
• The security model is a framework built from other studies,5 not a test of whether any particular new relationship will help you.