The study surveyed over 300 couples about their marital stress—things like how often they felt let down by their partner or how often their spouse criticized them—and their symptoms of depression. Then, nine years later, they repeated those surveys with the same couples. They also asked participants to undergo emotional response testing, which basically involved measuring each person’s frown muscles as they looked at a mix of negative, positive, and neutral photographs. The connections were startling: participants who reported the highest marital stress throughout the study also showed the most signs of depression. For instance, those with higher marital stress also smiled less at the positive photographs, an indication that they weren’t able to fully enjoy positive experiences—a hallmark of depression. Worth noting here is that the study only showed correlation, not causation. That means that while it’s absolutely possible (and makes some level of sense) that marital stress can make you feel depressed, it’s also possible that suffering from depression and depression-related symptoms might also impact the amount of marital stress that you report feeling. Depression is a serious disease that can have a negative impact on every area of your life, including relationships. Symptoms of depression include feelings of worthlessness, inability to experience joy or happiness, exhaustion, inability to sleep, and actual physical symptoms of pain—not to mention, the tendency to withdraw from loved ones and stop participating in the activities you used to love. Any of those symptoms could certainly result in more stress in your relationships. If you or a loved one are suffering from depression, you should take it seriously and make sure to get help for it. Here are tips for how to find a good therapist, and be sure to read our story Am I Depressed, Or Just Feeling Blah? And about managing marital stress: clearly, stressful things happen in marriages—and it’s important to learn how to work through your issues together, rather than let the problems pile up ceaselessly. There are tons of ways to divert marital stress, from talking through your problems or even just having sex more regularly. We have some of your other common marriage problems solved here.