There’s no need to worry if you think your partner is better-looking than you are.Most people, in both heterosexual and same-sex relationships, have the same idea. In fact, it’s a sign of love. You’re probably about equally attractive. And your partner probably thinks you’re the better-looking one.In theory, we’d all want the funniest, fittest, most fabulous mate. In reality, most of us wouldn’t be happy with someone we felt was far more attractive than ourselves. Could you really live with George Clooney? Brad Pitt? Jennifer Lopez? Maybe not.

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“The more similar two people are, the more likely they are to form a stable, lasting relationship and be happy with each other,” says Dr. Viren Swami, a Reader in Psychology at the University of Westminster, and YouBeauty Attraction Expert. We also like to think that a relationship is fair, with both partners doing well. As Swami puts it, “I don’t want to lose out, but I don’t want my partner to lose out, either.”We tend to choose partners with roughly similar levels of education, IQ, socio-economic background—and looks. However, love is indeed a little blind, Swami and others have found.

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The more in love you are, the more likely you may be to hold illusions about your lover’s appeal. Our mates look better to us than to others—an effect that researchers call the “love is blind” bias.Researchers aren’t sure why love is blind, but they have a few theories. Believing your partner is more attractive might make you more likely to put effort and energy into the relationship, or it might bolster feelings of love and soften any negative feelings. And of course, it can be an ego boost to think that you’ve won a hottie.Your partner, ideally, thinks he or she is getting the better deal.There is some evidence that extraverted people are even more likely to positively perceive their partner’s physical attractiveness, Swami says. And there’s some science to back up the idea that finding your partner more attractive than yourself is associated with a greater chance of a committed, passionate, intimate, satisfying relationship.

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Although romantic illusions do fade over time, the idea that your mate is more attractive persists even after many years. This emerged, for example, in a study of 93 heterosexual Dutch couples that had been together, on average, fourteen years. The people in the study tended to rate themselves a bit less attractive than their partner did. “People are often more self-critical about their appearance than they need to be, at least when it comes to their partner,” report researchers Pieternel Barelds-Dijkstra and Dick Barelds at the University of Groningen, in The Netherlands.We also inaccurately presume what our partners will find attractive. Studies have shown that both women and men tend to overestimate the importance of sex characteristics to potential opposite-sex mates. Women typically assume that men prefer a female shape that is thinner and bustier than they actually do, while men wrongly assume that women prefer heavier, more muscular and larger-chested men.

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In the end, both women and men tend to get hung up on looks. However, when it comes to attraction, “I have a feeling that physical attractiveness is a lot less important that you would think,” says Swami. And if you have a bad hair day or see a new wrinkle appear as if out of nowhere, remember that your partner is likely to see right past it with rose-colored glasses.

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