Tell me these three things about your relationship, and I can tell you if it’s going to last. Psychologists have figured out pretty accurate relationship math.

Dawid Zawiła

Are psychologists fortune tellers?

Well, if one of the purposes of psychology is to understand (and thus predict) behaviour, yes, there’s a little bit of fortune telling involved.

Not all psychology is about predicting the future, but if you give a sex and relationship researcher a few pieces of information, they’ll be able to tell, rather accurately, how strong your relationship is and how likely you are to stay together.

Trust me, I didn’t want to listen to these theories at first. They sound so… callous. In these models, relationships are a combination of risks and rewards, of contributions and benefits. They see relationships as mostly transactional; that is, people enter relationships because they get something out of it, usually more than they give.

Okay, Ani. But what about love? you ask. Sometimes we stay with people because we just love them even though we get nothing out of it.

Well, I wouldn’t call “love” nothing. But think about it for a second. Would you really stay in a relationship if you got absolutely nothing out of it? Like, not a thing, not even a feeling of security or commitment? Would you enter in a relationship with a perfect stranger who will just ignore you? Because that would be a relationship where you get nothing.

There’s actually debate about whether altruism truly exists, but few of us stay in romantic relationships for altruistic reasons. Guilt, dependence, “for the kids”, financial security, sure… but altruism? Not so much.

So, what makes us stay with partners? While there are theories about commitment (something I can discuss in another post), that’s not what I want to write about today. I want to focus on the big picture: the model that takes pretty much everything into account. It’s a little bit rough, it seems simplistic, but apparently it’s accurate and predicts the longevity of relationships very well.

This specific model is called interdependence theory, but I’ll try not to bother you with too much psychological jargon.

The variables

Interdependence theory has three variables: comparison level, comparison level of alternatives, and current outcomes.

Your comparison level (CL) is what you think you deserve, or what you want out of a relationship. Comparison level of alternatives (CLalt) is what’s available to you outside your current relationship. Current outcomes is what you’re actually getting.

Some of these break down a little further. Your outcomes are made out of your rewards – costs. Positive outcomes mean that what you get out of the relationship is worth more than what it costs you to be in it. Of course, rewards and costs are different for everyone. For me, costs are things like less time for myself, energy used socializing, and emotional labour. Rewards are intimacy, connection, sex, someone who listens to me, support in tough times, etc.

Whether you’re satisfied or unsatisfied with your relationship depends on what you believe you deserve. You could have positive outcomes with someone, but even those positive outcomes are not enough to meet your expectations. If your comparison level is higher than your outcomes, you’re going to be unsatisfied. If your outcomes are equal or greater to your comparison level, you’re going to be satisfied.

How dependent you are in a relationship is based on your outcomes and your comparison level for alternatives. Alternatives DO include being single, by the way! It isn’t always another relationship. Sometimes being single is better than staying in a bad relationship. If your outcomes are better than your alternatives, you are rather dependent: whatever’s out there is worse than what you’re getting. However, if your alternatives are better than your outcomes, you’re independent: you don’t necessarily need your partner around because you can do better elsewhere.

To recap: we’ve got CL (what you want), CLalt (what you could get elsewhere) and current outcomes (what you’re actually getting). These three variables are used to determine how stable and happy your relationship is.

The equations

Although there are 6 different possibilities, there are actually only 4 types of relationships in this theory. You’ll see why right below.

Miller (2015), p.181

In this model, relationships are evaluated on their happiness and stability. Obviously, a relationship is unstable if there are better options elsewhere, and it’s unhappy if you don’t think you’re getting what you deserve.

If your outcomes are better than both your alternatives and what you think you deserve, you’ll stick around. If your outcomes are worse than both your alternatives and what you think you deserve, your relationship is not going to last much longer.

The tricky stuff happens in the middle: when one OR the other is better than your current outcomes. You can be happy (outcomes better than CL) but see something better elsewhere: in this case, you’re probably going to jump ship at the earliest opportunity. However, you can have a crappy relationship, but because the alternatives are worse, you’re going to stay anyway.

The results

Here’s the thing, though: everyone’s got different expectations and beliefs about what makes a good relationship. So you’re the only one who can tell whether your expectations are being met in your current relationship.

For example, I could only leave M. when I realized that alternatives—any alternative, really—were better than my current outcomes. For a long time, singlehood was not viable, but it became so once I realized that if I stayed, I would never ever have a satisfying sex life. Even the financial penalty of living alone didn’t seem so bad once I adjusted my comparison level and redefined what I believed I deserved.

Your concept of what constitutes a viable alternative can change with time: an extreme example would be finding the gentle but ugly neighbour more compelling once your current partner starts beating you. (It doesn’t have to be that bad, but you get my point.) So can your concept of what you deserve. A person with low self-esteem will put up with a lot of shit because they don’t think they deserve better; send them to therapy and have them improve their self-esteem, and they’ll quickly adjust their expectations accordingly.

There’s also people who think they deserve so much that they will never find anyone who will fulfill their expectations. You can desire to have a relationship with only the hottest, richest and kindest people, but will you ever find that particular combination with anyone, realistically? These people are chronically unsatisfied. Nothing will ever make them happy enough.

Another problem is that we get used to certain outcomes, and over time they don’t seem as good as they used to. A partner who makes you breakfast in bed every week is awesome… at the beginning. After a few years, it just doesn’t have the same effect, and the relative benefit of this particular perk will go down in your mind.

Apparently, this model is the best at predicting relationship longevity. However, there’s (yet) another crux: people are rarely neutral enough to evaluate their own relationships, especially their outcomes. Because of a bunch of biases, we make ourselves believe that things are better than they are because otherwise we’d have to reevaluate a lot of our decisions… and we don’t like that. That’s why hindsight is always 20/20: we’re not so involved in past decisions anymore.

Final words

So, what can you do with this theory? Well, I hope it gives you an interesting perspective on how psychologists actually explain romantic relationships. It’s given me a more abstract, detached way to look at past and current relationships, and it’s helped me explain a lot of past behaviour that I will hopefully not repeat in the future.

Also, I hope it will encourage you to take a good look at where you stand in the above graph. Are you really getting what you want? Or are you sticking around just because there’s nothing better out there?

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Good advice? Helpful information? Thank me with a coffee!