Young people searching for a romantic partner sometimes look for a mirror image of themselves. Someone who shares every taste and belief. That’s not only unrealistic but probably not the basis for a healthy relationship. Still, there is typically a certain compatibility required for a relationship to thrive. You may have the same values (a fundamentally important requirement), share a desire to create a family, enjoy the same recreational activities and food. All good things — some more important than others. If you’re in a relationship and can list many things, including the important ones, that you share as a couple, then you probably have a solid basis for building a future together.

But here’s one thing that you may not have in common, and it might affect every other aspect of your relationship: you might not have the same basic disposition. One of you might be naturally sunny and positive, thinking that every cloud has a silver lining — while your partner sees every glass as half empty.  

If this is the case, and you’re the cheerful one in this scenario, then the temptation may be to simply excuse your partner as being a lovable grump. But not so fast. Your partner’s grumpiness may affect you more than you’re willing to admit. Writing for Psychology Today, Wendy L. Patrick, Ph.D., delves into the implications of recent research conducted by Olga Stavrova and William J. Chopik (revealingly published in a study titled “Don’t Drag Me Down”). The study explored the idea that each partner in a couple influences the other with their mood. Patrick writes that the study “found that happier partners experienced the most dramatic decline in well-being, while unhappier partners experienced only a slight improvement in their well-being, if anything. Stavrova and Chopik note that their results illustrate a negativity bias in well-being co-development — that ‘bad seems to be stronger than good’ in shaping the dynamics of changes in a couple’s well-being.”

Consequently, the study continues, “Because the brain’s negativity bias gives negative information more weight than positive information in affective experiences, it might give unhappier partners more power to influence interactions and overall affective experience, allowing negativity to dominate daily conversations.” To put it simply, someone in a negative mood can bring their partner down more than the happy partner can bring ol’ sourpuss up.

So, how does a happy and cheery partner avoid having their partner put a damper on the day? Patrick has three tips.

“Creating Positivity.” Being upbeat doesn’t mean denying reality. Yes, bad things do happen. The trick is to acknowledge all the rotten things that may have happened without letting them turn you into a hopeless pessimist. Patrick suggests setting a time out each day to look the negative right in the face. However, you don’t want to get trapped there — designate “a time to discuss negative events of the day — with both a start and an end time,” Patrick says. “This ensures a negative partner has the opportunity to vent or share unpleasant feelings but within a reasonable time constraint to ensure the negativity does not dominate the household. More time should be spent discussing positive topics, both before and after the vent session.”

“Misery Should Not Love Company: Maintaining Boundaries.” If you designate a time to acknowledge the negative, then you (the happy one) need to insist on keeping discussion of and comments on lousy situations restricted to that time frame — which is a boundary both of you need to respect.

“Focus on the Future.” What’s done is done, as the old saying goes. Believing that, though, brings up a question: what now? This can and should create a wonderful opportunity. Patrick describes this opportunity, saying, “Because achieving hope and happiness is often about a perception of control, happy partners can optimize optimism through proactively planning the future, incorporating plenty of events and plans that make both partners happy and hopeful.” If the happy partner shines a bright light on the future, it may very well be what their grumpy other half needs to enjoy life with a smile on their face.