At one time or another, many people have felt the urge to cheat on their partner with their co-worker or cute stranger at the bar. Infidelity is a sad reality some relationships face, and it leaves the betrayed partner wondering why such a thing happened. A recent study published in the Journal of Sex Research suggests Millennials are more likely to cheat for reasons relating to independence and interdependence.

Researchers from the University of Tennessee noted a majority of 20-somethings in their study committed infidelity for "interdependence" reasons, with a majority of those participants cheating because they felt a lack of intimacy, including poor communication, lack of spark or feeling loved, in their relationship. Meanwhile, the other group of cheaters betrayed their partners because they desired a sense of independence, (i.e., identity, autonomy) they weren't getting. Cheating in this age group was most common because emerging adulthood is a developmental stage where Millennials are trying to sort life out, researchers said.

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"[I]t is possible that engaging in infidelity is a path through which individuals seek to meet their developmental needs for independence and interdependence and promote their individual development," Jerika Norona, lead study author, graduate student at UT and current psychology intern at the San Francisco VA Medical Center, told Broadly.

People in their 20s may use cheating as a way to establish their independence as adults, while others have used it to find interdependence in their relationships. These types of cheaters know what they want out of love and life, but they don't know how to achieve it, so they get by trying to figure it out. Cheating is one way they go about this "self exploration" phase.

Previous research has found it's taking young adults much longer to become proper grown-ups. During a 2013 TED talk, clinical psychologist Meg Jay warned 20-somethings should not treat this period as a "throwaway decade", but to start planning for their lives as soon as possible. Her advice focused on finding the right partner as soon as possible, and Jay suggested people in their 20s aren't moving forward with their lives because they're lazy and indecisive.

Many Millennials, however, are struggling to find jobs that allow them to earn enough to pay rent. This places an economic burden on top of the emotional burden they may feel regarding life goals they're not even close to achieving. Therefore, through a transition period, they also become incapable of maintaining healthy intimate relationships because they're mentally and emotionally struggling.

However, this is no excuse for cheating.

In the study, researchers surveyed 104 heterosexual adults who on average were 22 years old and reported cheating within the last six months. Before the survey, participants were given a paragraph to read that shared how typical cheating is to help them feel more comfortable discussing the nature of their affairs. The researchers asked participants to give details about their current and past romantic experiences, often with a written account why they chose to be be intimate with someone else other than their boyfriend or girlfriend, along with how attached they were to their partners.

Seventy-six people cho se interdependence reasons for cheating, while 21 people felt their need for independence motivated their betrayal. Other reasons for cheating included alcohol consumption and looking for a thrill. But, attachment styles also played an influential role in infidelity.

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Researchers identified two different relationship attachment styles that were related to cheating. First, people who avoided getting too close were more likely to believe their partners weren't meeting their needs, and second, people who worried about losing closeness with their partners were more likely to push their partners away by saying they weren't being given enough space. These two attachment styles are fear driven.

Overall, it seems 20-somethings cheat because they struggle with managing their desires and goals in the context of a healthy relationship. However, cheating happens at any age — no matter if you're 26 or 66. A study in May found the average age a married woman cheats is 36.6 years old, which implies fidelity and passion begin to dissipate 6 to 7 years after the wedding — 29 is the average age of marriage. This could be due to factors like not receiving enough attention and respect from their partner as they feel they deserve.

The bottom line: Cheating is never okay or normal, but breaking up is. If the relationship is not working, move along.

Source: Norona JC, Olmstead SB, Welsh DP. Betrayals in Emerging Adulthood: A Developmental Perspective of Infidelity. The Journal of Sex Research. 2017.

See Also:

A Cheat Sheet For Everything You Need To Know About Infidelity

High Internet Use May Lead To Risky Behavior, Emotional Cheating For Couples