In the age of social media, it’s become totally normal to keep tabs on people we don’t know, like they’re little Sims characters in our lives. But why do people drive themselves crazy doing this with their partner’s ex? Honey Wyatt investigates.

Since the dawn of time, it’s been hard-wired in us to check out the competition. Centuries of hard work has fine-tuned our brains to collect every piece of information out there to allow us to win over a mate with bigger balls, brighter feathers, or a deeper mating call. 

Today, rather than mentally listing off the threat of various flora or fauna, we have everything we need to tally up our strengths and weaknesses right at our fingertips. Gigabyte upon gigabyte of data exists that allows us to piece together a puzzle of who our partner dated before us, from their clothing size and their job, to how many close friends they have, and where they went on their latest holiday.

Going down this rabbit hole is a treacherous path; one that, as a chronically avoidantly attached dater, I haven’t felt inclined to tumble down. Preferring to remain oblivious of the threats to my relationships, I have been entertained many a time when hearing how my fellow twenty-somethings employ MI5-like sleuth in uncovering benign snippets of information about their partner’s ex. 

Alexandra*, 24, tells me that around a year into her now five-year relationship, she suddenly became conscious of the fact her boyfriend had dated someone before. “Suddenly I was like, ‘shit, I should Google her’, and then I found all her friends,” she admits. 

To start with, she went down the usual routes – Instagram and Facebook – but these were private accounts. So she was forced to move on to more devious methods like LinkedIn and Depop, sometimes using a fake account or a private browser to see what she was up to.

At the peak of her obsession, she was checking every night before bed. “But now I only do it when I’m really bored, maybe once a week at the weekend,” she says. Considering the emotional energy it would require to keep tabs on someone you don’t know, I couldn’t help but channel my inner Carrie Bradshaw and wonder: where does this obsession come from? Is it more common in anxiously attached people, or does that have nothing to do with it at all? 

Ronald Hoang, a family therapist and marriage counsellor, says that it could be linked to anxious attachment because it exhibits jealousy (a common feeling experienced by those with this attachment style). 

“[Jealousy] lends itself to clinginess and to becoming fixated with the current partner’s ex, because they may think, ‘the more I understand your ex, the more I understand you’.” he explains. But this kind of thinking is not necessarily accurate. “Jealousy drives partners to believe that full transparency gives way to trust, but it also gives way to surveillance. Trust is about being able to sit with uncertainty,” he advises. 

Being preoccupied with your partner’s past can also be a sign of insecurity, explains relationship therapist, life coach, and founder of Miss Date Doctor, Nia Williams. Again, this is a common side effect of anxious attachment. “Individuals may feel insecure about themselves or their relationship, leading them to compare themselves to their partner's ex,” she says. “This can be driven by low self-esteem or a fear of not measuring up to a perceived standard.” 

Alexandra describes feeling insecure when she first started looking at her partner’s ex. “It used to make me sad and I would cry because I thought I was fat and ugly and less cool [than her],” she reflects. When probed why she did it, if it made her so miserable, she explains: “I used to think my boyfriend thought I wasn’t cool enough for him, but now I don’t care and I know I’m better than her probably because it’s been like five years.

“My worst time was between the second and third year because they dated for two years, and I felt like I still hadn’t established that I was more of his girlfriend. Once I overtook their time, I felt more confident.”

Williams describes how, when this insecurity combines with not feeling in control of a situation, they might want to dig further into their partner’s past to understand them better. “Some people find comfort in knowing details about their partner’s past relationships,” she says. “The fear of the unknown, combined with a desire for control or certainty, may drive them to gather information about their ex-partner.”

Listen: Why Learn Your Attachment Style?

For Lily*, 23, this lack of knowing is what drove her to want to find out more. “My ex talked about [his ex] a lot, I think he wasn’t fully over the relationship when we met and I just knew lots of random facts about her, which made me want to know more,” she remembers. 

Because Lily didn’t trust what he was telling her, she developed what she describes as an “unhealthy” fixation on his ex. “I didn’t trust how he said he felt about her,” she comments. “I found her nudes on his phone, knew they were still texting when we met, and he lied about them having a clean breakup, so I was almost keeping tabs on this person because I felt threatened that she could directly impact our relationship.” 

Regardless, she acknowledges that this wasn’t anything to do with the ex. “If an ex can do that it’s not really their fault, they don’t owe you anything. It’s more about your partner,” she observes. 

In her current relationship she feels much more secure in the relationship as a whole, so doesn’t feel so compelled to check on his exes. “It turns out when you’re with someone who treats you well and that you trust fully, it’s actually hard to feel insecure about other people potentially ‘stealing’ your partner,” she laughs. 

Having dated people of multiple genders myself, I somewhat understood why some women snoop on their boyfriends’ exes. In the same way we send pictures of men to our friends before going on a date, conducting a full background check on them is in many cases a form of self-protection. They’re checking that their boyfriend isn’t still dating his ‘ex’ behind your back; that he’s not about to run back to ‘the one who got away’ (stay tuned for another article on men’s obsession with that); or that he’s not secretly cheating on you with five other people.

(Interestingly, I couldn’t find any straight men who reported keeping tabs on people via social media, although one of my gay friends once found a man he had exchanged around three words with at a cafe on Instagram. Maybe it’s a skill reserved for the girls, gays, and theys? Or maybe they’re just more willing to admit to doing it.)

Despite my suspicions that this obsession is more common among women who date men, Noah*, 23, suggests this is not the case. A couple of months into her relationship, she developed a fascination with her girlfriend’s ex. “I was just obsessed – I wanted to know everything – and I think it’s because there’s a lot of lore around her,” she theorises. “I was like, ‘I need to know more, I’ve never met someone or heard of someone who has all these contrasting things around them’.” 

Going down the usual Instagram and LinkedIn routes, she found nuggets of information, like that she was a girl guide for several years. What struck her most, though, was how different this person looked to her. “I had such a horrible feeling because I was like, oh, she’s hot but she looks nothing like me. She’s very blonde, very curvy with big boobs and I’m like no! That’s nothing like me. I went through a crisis where I was thinking, ‘is that what my girlfriend likes? Is that what she’s comparing me to?’.” 

Read more: How to heal anxious attachment style, according to experts

A 2023 study found that, while lesbian and bisexual women feel less inadequate than heterosexual women when it comes to their body image, lesbians report higher levels of self-hate and self-attack than bisexuals and heterosexuals. Bisexuals in same-sex relationships can also compare themselves more to their partner, so this kind of comparison based on body image is not uncommon.

After talking to her girlfriend about it, Noah says the ex became “less of a mysterious entity”, which somewhat quelled her obsession with wanting to find out more about her. Nonetheless, she describes still having a semi-parasocial relationship with this woman, simply due to knowing so much about her.

“I almost feel a kinship with her and there’s this feeling of ‘we’ve shared something so fundamental because we’ve been with the same person’. The reason [my girlfriend] is who she is now is because she’s been with this person. 

“On some level, I feel solidarity with her. Even though I’ve heard she’s not a very nice person, I’m still rooting for her and hope she’s ok and everything works out for her.”

Both Alexandra and Lily echo this sentiment, saying that they can imagine being friends with their partner’s exes in a different life. Because of this, Alexandra doesn’t see herself stopping checking any time soon. “I feel like I know her, it’s more out of curiosity now because I know he doesn’t like her.”

Hoang asks whether this compulsion to check in on someone you don’t know could be linked to how the neurochemistry of our brains reacts in a break up. “Neuroscience has unveiled that the areas of the brain that are activated during breakup are the areas responsible for physical pain as well as craving or addiction.  

“This is why we can't stop thinking about our ex after a breakup or why we feel compelled to get back with them. I wonder whether this process is inadvertently occurring with a new partner becoming fixated on an ex of a current partner.”

So next time someone questions where this obsession comes from, you can be safe in the knowledge that it’s not you, it’s neuroscience. And once those negative feelings around the addiction go away, it seems like you have a nice little (albeit one-sided) relationship with your partner’s ex. As Noah says: “I don’t just feel like, ‘I hate that bitch, I want her dead’, it’s more like, ‘I wish her well’, you know?”

Personally? I’ll sit patiently with the hope that one of my exes’ future partners out there feels that way about me. 

*names have been changed