Relationships are hard to stay in, but often even harder to leave. Sometimes, even the worst relationships can be difficult to end, and there may be a psychological reason behind this commitment to failure. According to a recent study, our reluctance to leave a relationship that isn't working may be due to the ‘sunk cost effect,’ where we feel that if we’re going to waste time doing something, we may as well stick it out, no matter what. How romantic.

A recent study gave 1,000 volunteers different hypothetical relationship scenarios in order to gauge exactly what it would take for them to leave a marriage. Results showed that despite being in a loveless, sexless marriage, 35 percent of people who had hypothetically invested money and effort would stay with their spouse. On the other hand, 25 percent of people admitted they'd leave a marriage if it was still new and if they hadn't put in much effort. Based on these results, the researchers concluded that it takes more than love to keep a couple together.

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"Together... experiments confirmed the initial hypothesis that investments in terms of time, effort and money make individuals more prone to stay and invest in a relationship in which they are unhappy,” concluded the study.

For the research, the team split up the volunteers into four groups, giving each a different hypothetical relationship status. The first group was told only that they were in a loveless marriage; the second group was told they were married for a year; the third was told they had bought a house with their spouse; and the last group was told that they had put a lot of effort into trying to fix the marriage, Her reported. Trends showed that the more time and money invested in a relationship, the less likely an individual was to end it.

According to WhatIs.com, the sunk cost effect is the tendency for humans to continue investing in something that clearly isn’t working. This is because it’s in human nature to avoid failure, so we are programmed to spend time trying to fix something rather than starting something new from scratch. This psychology isn’t restricted to our love lives, and can dictate many of our life choices.

Source: Rego S, Arantes J, Magalhães P. Is there a Sunk Cost Effect in Committed Relationships? Current Psychology . 2016

See also:

Fear Of Loneliness Explains Many Bad Relationships

Impulsive Behavior In Romantic Relationships Linked To Happiness