In this post, we will look at the top ten signs someone is lying about cheating.

In the context of romance and infidelity, “cheating” is not a particularly accurate label. Cheating is defined as an act of non-consent. Although there is some overlap with “non-consensual sex” – as there can be both consensual and non-consensual sex – for the purposes of this discussion, cheating should be defined more broadly to include acts that are not explicitly sexual.

This post is based on my book “ Lying to Yourself About Cheating. The Science Behind How We Lie To Ourselves About Sex and Romance .” It’s not a comprehensive list but I hope it will inspire you to think about how you can use it (and any other tools you have) when you are in a relationship with someone who might be cheating on you.

They avoid being around you

Cheating is a tricky thing to prove. In fact, there are no easy tests to give you whether or not someone is cheating on you. We can ask: “Is the person sleeping with another person?” or “Does the person have a new girlfriend/boyfriend?” These tests may be useful for some people, but they don’t necessarily tell us whether someone is cheating on you. For example, if you suspect your boyfriend is cheating with another woman, you could ask him if he went out with her last night and/or why he didn’t stay home last night:

What if he says he was out for dinner and didn’t want to come home because he was tired? If that happens, then it’s probably not true. But if it doesn’t happen that way, then it definitely isn’t true. You can also test your boyfriend and husband by asking them what they are doing at the moment and giving them specific instructions as to what they should do next (e.g., “Go shower and come back so we can talk about what happened last night.”).

If neither one of these tests leads to a testable answer — i.e., if your partner tells you whatever story their mind will conjure up — then most likely they are lying about their actions from earlier in the evening or even earlier in the week when they came home from work and are lying now because they have nothing else better to fill the time.

You may have a lot of questions right now: What do I do? What should I do? How do I find out? How can I trust my partner again? Should I believe her again or should I try me again too? The above list is just scratching the surface of the many questions we hear all day long on a daily basis from our clients (and quite often even from our own teammates). As we have found over many years working with thousands of people in all kinds of relationships, here are some common questions that people ask us every day:

Where did it go wrong this time? What went wrong this time? 

They stop including you in their plans

Everybody needs that one friend, not feeling left out when they are away on a business trip, or at the beach or something. It’s not unreasonable to ask: “Why are you leaving us out of your plans?” This is a sign that someone is lying about cheating.

A key question to ask yourself: “How much have I invested in this person?” There is a difference between being included and being part of what they do. If they don’t talk to you about their plans and work, and you feel like they aren’t investing in you, it might be that their investment isn’t even worth your investment (which isn’t true for all people — some people invest more than others).

Another question to ask yourself: “What does my life look like without this person?” This may sound obvious, but a lot of people just cut off communication with their friends because it feels too painful. If you think this person is hurting your friendship with someone else in the same way, then perhaps it would be best for both of them if you stopped communicating with them too.