The Erosion of Intimacy: Dealing with the Dark Side of Relationships

Cheating and the collapse of connection.

Love is supposed to be perfect, simple, and always amazing. Except it isn’t.

Infidelity may be the ultimate relationship betrayal.

As a client once described, “It didn’t happen overnight. One day we were laughing in bed, and the next we’re sitting in silence at dinner, wondering how we got here and when the emptiness crept in.”

Intimacy doesn’t end with an explosion, but more often, with erosion.

Most couples feel it at some point: emotional disconnection and distance. Most also dismiss those feelings as inconsequential or ignore them, hoping they’ll pass. Unfortunately, as intimacy withers away there are consequences for relationship well-being (Finchem, 2017). When a relationship is no longer satisfying, it provokes one of the darkest relationship behaviors of all: cheating.

Admittedly there are lot of “dark” behaviors to discuss, but infidelity is the ultimate relationship violation, and one of the most notorious relationship killers. Because of that, we’re going to focus on 1) why people cheat, 2) who is most likely to get cheated on, and 3) how to catch a cheater.

8 Reasons Why People Cheat

All affairs aren’t created equal. Some are brief trysts of convenience and circumstance, others are longer calculated affairs (some are inappropriate field trips to a Coldplay concert with a work “friend”). It all hurts. So, why are partners unfaithful in the first place?

The most common approach is to diagnose what’s missing from the relationship, especially sexually. But that type of blame game is an oversimplification that misses many other culprits. Research found that only half of cheaters reported having intercourse (Selterman et al., 2020). Yes, sex is part of why people cheat, but what else is going on?

Lots of reasons. The same study sampled 495 cheaters to understand why they did it. The analysis revealed eight key motivations, most of which didn’t involve sex at all. Many said they cheated due to anger, lack of love, low commitment, esteem, situation, and neglect. Importantly, the reasons why they cheated not only impacted their affairs but their primary relationship as well.

For example, cheating motivations influenced the length of affairs. When people cheated due to anger, lack of love, or variety, their affairs were longer, while those motivated by the situation had shorter affairs. Women also had longer affairs on average than men.

In the affairs, roughly 4 out of 10 (37.6 percent) had intimate conversations, while 1 in 10 (11.1 percent) said: “I love you.” Those who reported less emotional connection in their primary relationship had more intimacy with their affair partner, perhaps as a way to seek out missing fulfillment. Similarly, when lack of love prompted the affair, individuals found the affair more intellectually and emotionally satisfying.

When your primary relationship doesn’t fulfill your needs,

you’ll find someone who does.

Again, it wasn’t all about sex. much of the cheating sexual activity involved kissing (86.7 percent) and cuddling (72.9 percent). Oral sex (46.4 percent), vaginal sex (53.3 percent), and anal sex (6.1 percent) were less common. Some had no physical contact (6.7%).

Do Some People Want to Get Caught?

We typically think of cheating as a clandestine enterprise, with the whole point being not getting discovered. But some cheaters aren’t as careful as others, perhaps intentionally. Those cheating due to lack of love went on more public dates like going out to dinner or the movies. Kissing in public and other public displays of affection were more common for those motivated by lack of love, wanting to boost their own self-esteem, and those seeking more variety. Again, not exactly secretive behavior. Perhaps these cheaters felt more justified in cheating (i.e., less guilty), or perhaps the affair was an exit strategy or a way to force changes in the primary relationship.

In fact, many cheaters confessed their affair. There was almost a 50/50 split between disclosers and secret-keepers. Women were more likely to fess up than men. Overall, those who came clean were more likely to have cheated initially out of anger or neglect, and not because of sexual desire or variety. Those motivations suggest that the confessions were likely a form of retribution and more about being nasty than noble. However, those who came clean were also more likely to form a committed relationship with the affair partner (in other words, they had to tell because they were likely trying to move on to another partner).

In your relationship, you don’t get to decide whether you cheated or not.

Your partner does.

What Happens after Cheating?

Funny thing about that is the affairs rarely resulted in real relationships with only one out of 10 of the affairs ultimately turning into a full-fledged committed relationship (11.1 percent). More commonly, cheaters only saw that person occasionally (31.1 percent), with another third (29.9 percent) staying friends with their affair partner, and the remaining 25.5 percent shutting the affair partner out and having no contact with them.

For the primary relationship, surprisingly only 1 in 5 (20.4 percent) ended because of the affair. Near equal numbers (21.8 percent) stayed together despite their partner finding out, while slightly more (28.3 percent) stayed together without ever discovering the infidelity. The remaining relationships broke up for non-cheating related reasons.

Who Is Most Likely To Get Cheated On? Personality Matters

To figure how why some people keep getting cheated on, researchers collected data from 1,577 adults, including 898 married individuals, the study found that those who were less responsible, organized, or hard-working (i.e., they scored lower in conscientiousness), were more likely to have experienced infidelity (Mahambrey, 2020). Among married participants, higher agreeableness also predicted greater likelihood of being cheated on, possibly because warm, forgiving individuals may make it easier for cheaters to rationalize their behavior. To be clear, this isn’t intended to blame the victim but rather highlights qualities make some people more tolerant or forgiving than they should be.

How To Catch a Cheater: Following the Digital Breadcrumbs

To create this section I did a deep dive into “How to Cheat without Getting Caught” resources (yes this exists…the internet is a crazy place). I reverse-engineered what I found to create this list.

A lot of “how to catch a cheater” is obvious stuff you’d already know, such as physical evidence (e.g., a fake eyelash, unfamiliar bobby pin, or faint lotion or perfume…and of course glitter) or sudden changes in behavior (e.g., sudden new gym routines, "work trips," aesthetic purchases like clothes and cologne, or guilt-driven gifts.)

What I thought you may not be as familiar with are all of the tech-related ways to detect cheating. Here’s the “Top 10” techniques you can use:

1. Phone Guarding - A partner being secretive about phone use, making it hard to see their screen, and not ever leaving their phone unattended can be red flags.

2. Wi-Fi Never Lies - Check the router logs for unknown or frequently connected devices. (For anything you don’t know how to do like “checking router logs”, Google it)

3. Look at Device Sync Activity - Apple ID or Google accounts often log every device connected. Unknown devices are a red flag.

4. Check Bluetooth and Car Pairings - See what phones have connected to their car or laptop via Bluetooth.

5. Look at Location History - Google Maps or Apple’s “Significant Locations” reveal movements and patterns.

6. Analyze Browser and Search History - Searches, autofills, and browsing habits can expose hidden interests and people.

7. Check Cloud Backups - Deleted messages and photos often remain in iCloud or Google Drive if syncing is on.

8. Monitor Installed and Deleted Apps - Watch for secure messaging apps like Signal, ProtonMail, or Telegram suddenly disappearing.

9. Track Digital Payments - Check for small transfers to Venmo, Cash App, or strange charges from rideshare services.

10. The Nuclear Option - Use spy or tracking software Apps like mSpy or Spyic to monitor texts, calls, and hidden apps without detection.

An important practical note. Yes, you can (and in some cases should) play digital forensic evidence detective. But if you’re willing to go this far, what does this really say about your relationship? To me it says you need to have a conversation with them…and not to accuse them, but to discuss the state of your relationship (for help with that, here’s a previous article on communicating better.)

Conclusion

Overall, cheating isn’t as simple as seeking out sex. In particular, there appear to be two main motivators for cheating: the situation and a broken relationship (i.e., lack of love). It all emphasizes the importance of strengthening our relationship’s emotional connection. Not only will that negate a major motivation for infidelity, but also help us have a more satisfying and committed relationship.

BONUS: Here are some other cheating topics you may find interesting…

• To learn more about the biology of cheating, click here.

• If you’re interested specifically in why women cheat, check out this article.

• Curious about what counts as cheating and the fuzzy gray areas? “Microcheating” is for you.

Know someone else who should take this “course,” enjoys psychology, has a relationship, or hopes to one day? Please refer them here:

Here’s what you can look forward to:

The Psychology of Relationships 101 Curriculum

1. Is It Just Me? Or, Is This How Relationships Are?

2. Clarity Attracts Chemistry: The Power of Knowing Who You Are

3. The Flirting Formula: Science-Backed Strategies for Connection

4. The Science of Attraction: It’s Not Just Looks, It’s Psychology

5. The Science of Love: From Instant Chemistry to Lasting Connection

6. The Truth about Attachment: The Science of Secure Connection

7. Sex Ed 2.0: The Conversations We Missed

8. The Science of Communication: What Builds Connection and What Breaks It

9. When the Spark Fades: Feeling Adrift in Love

10. The Erosion of Intimacy: Dealing with the Dark Side of Relationships

11. Happily Ever After or Single Again: Does My Relationship Have a Future?

12. The Foundation of Forever: Simple Strategies for Enduring Connection

13. Break Up Doesn’t Have to Leave You Broken

14. The Connection Code: Your Keys to Unlocking a Love That Lasts

References

Fincham, F. D., & May, R. W. (2017). Infidelity in romantic relationships. Current Opinion in Psychology, 13, 70–74.

Mahambrey, M. (2020). Self-reported Big Five personality traits of individuals who have experienced partner infidelity. Personal Relationships, 27(2), 274–302. https://doi.org/10.1111/pere.12315

Selterman, D., Garcia, J. R., & Tsapelas, I. (2020). What do people do, say, and feel when they have affairs? Associations between extradyadic infidelity motives with behavioral, emotional, and sexual outcome. Journal of Sex & Marital Therapy, 47(3), 238–252. https://doi.org/10.1080/0092623X.2020.1856987