Discovering Infidelity on Facebook

How do people react when they uncover their partner’s unfaithfulness on Facebook?

Who knows what this couple are up to on their laptops? Probably just playing Solitaire… CGP Grey/Flickr

Social media apps connect us with friends and family even when we’re physically separated. Whether organizing events and get-togethers, sharing baby photographs with grandparents who live overseas, or simply updating our social circle about our feelings and activities, social media clearly serves an important purpose for hundreds of millions of people.

But, as we all know, social media offers the opportunity for negative as well as positive behaviors. The relative anonymity of some social apps, and ability for anyone on the network to contact anyone else, means that trolling and abuse can quickly escalate. And the ease with which we can make connections, without which social media would cease to function, also offers opportunities for illicit relationship behaviors.

If you are caught cheating on Facebook, you can always blame it on this guy. Robert Scoble/Flickr

Put simply, the rise of social media has been a boon for those who are inclined to pursue extramarital affairs. With a pool of potential partners vastly larger than the number of people any individual could hope to meet in the real world, and ample opportunity for anonymous and furtive interactions, it shouldn’t be surprising if many are tempted to use Facebook to facilitate their infidelity.

Still, one drawback of sending sexualized messages to an affair partner is that there’s always the chance that your long-term partner will discover evidence of your transgressions. What happens then? How do we react? With social media a relatively new phenomenon, it’s unclear whether social rules that govern acceptable responses to online infidelity have emerged.

“I feel so bloody connected to you!”

Psychologists Michael Dunn and Gemma Billett of Cardiff Metropolitan University in Wales decided to investigate.

They had a group of student-aged and heterosexual male and female volunteers view mocked-up Facebook pages. On each page appeared a message. The volunteers were asked to imagine they had discovered this message in their partner’s inbox or outbox (see the image below for an example).

The researchers wrote these messages themselves. Two of the messages were intended to reveal sexual infidelity: that the partner was having sex with someone else. Another two messages revealed emotional infidelity: that the partner had a close bond with someone else.

Now, when scientists attempt to script naturalistic interactions for use in their research, the results are often less than impressive. When scientists study humor, they write jokes that would fail to elicit a chuckle from a six year old. When they study courtship, they write chat-up lines so hackneyed they would make James Bond blush. But here, Dunn and Billett have outdone themselves. I am no longer in my early twenties, I don’t use Facebook, and I am not a philanderer, so I am perhaps not the best judge of whether these messages appear genuine. What do you think?

The first message, which was intended to reveal sexual infidelity, was:

You must be the best one night f..k I’ve ever had! Last night was out of this world sexy bum! ;) x

The second sexual message:

Wish I could ride you again like last night babe! I’ve never cummed like that before! Ha x

The first emotional message:

I honestly don’t mind waiting to have sex! Not for a girl/boy like you :) You’re f…..g perfect baby xx

And the second emotional message:

You must be my soulmate! I feel so bloody connected to you, even though we haven’t slept together xxxx

After reading each message, the volunteers rated from 0 to 10 how distressed they would be if they found such a message in their partner’s Facebook messenger.

An example of a Facebook message seen the volunteers in the study. Dunn and Billet (2017)

The results of the study showed that women reported more distress than men when they imagined finding evidence of emotional infidelity, and men reported more distress than women when they imagined finding evidence of sexual infidelity. This supports the results of numerous previous studies that have shown much the same responses to imagined emotional and sexual infidelity, but without the Facebook component.

It makes sense for men to be more concerned by sexual infidelity. If a man’s partner falls pregnant, he can never be 100% sure that the baby is his. If he discovers his partner was sexually unfaithful, the baby could very well be someone else’s. If our male ancestors ignored this problem, they would not be our ancestors. Of course, women are also distressed by sexual infidelity, but the stakes are not so high: a woman always knows her offspring are her own.

It’s probably not a good idea to leave this lying about for your partner to find. Magicatwork/Flickr

It also makes sense for women to be more distressed than men by emotional infidelity. Declarations of love are often interpreted as evidence of a willingness to commit to a partner. Women, who are obliged to invest heavily in their offspring (pregnancy and lactation are expensive!) are generally attracted to partners who are willing and able to share the burden. If a man is committed to someone else, that could be a sign that he is diverting investment away from his primary partner and offspring. Again, this doesn’t have to be true of all women all of the time, but a partner’s emotional infidelity was likely a bigger problem for our female than our male ancestors, and we shouldn’t be surprised if women are adapted to resist such threats.

Who wrote that?!

The researchers also found that women were more distressed when they read a message written to their partner than by their partner. Men were just as distressed regardless of whether the message appeared in their partner’s in- or outbox. Why?

Previous research shows that women are less inclined to blame their male partner for infidelity than the other woman for stealing him. This is perhaps because women are seen as “gatekeepers” when it comes to short-term sex: if a man and woman contemplate a fling, it is assumed that the man is interested and that the woman will be the one to decide whether they go ahead.

As the researchers point out:

Understanding the mechanisms underlying jealousy is important as partner infidelity whether real or suspected has been implicated repeatedly in cases of domestic abuse and violence.

Dunn, M. J., & Billett, G. (in press). Jealousy levels in response to infidelity-revealing Facebook messages depend on sex, type of message and message composer: Support for the evolutionary psychological perspective. Evolutionary Psychological Science. Read summary

For an audio version of this story, see the 29 August 2017 episode of The Psychology of Attractiveness Podcast.

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