A relationship expert shares what she's learned from years of studying married and divorced couples.

By Real Simple
Updated June 12, 2015

Dr. Terri Orbuch is a research professor at the University of Michigan’s Institute for Social Research and the director of a landmark study, funded by the National Institutes of Health (NIH), where she has been following the same 373 couples for almost three decades. She is also the author of five relationship books, including 5 Simple Steps to Take Your Marriage From Good to Great. Since she began her study, 46 percent of her couples have divorced. Orbuch shares several sneaky, everyday behaviors that will chip away at any relationship.

1. Skipping “me time.” Successful couples from Orbuch’s study felt that time alone is the reason their relationships survived. While spending time together is healthy, it’s also important to find hobbies or activities that you can do on your own to cultivate your own interests.

2. Assuming you know everything. Don’t assume you know how your partner is thinking or feeling—instead, continue learning about your partner, no matter how close you think you are. “You want to always feel like you want to ask a question,” says Orbuch.

3. Sweeping pet peeves under the rug. According to Orbuch, happy couples actually do “sweat the small stuff” in their relationships. Small annoyances can develop into bigger problems over time, so it’s important to communicate and work through conflict, no matter how tiny it may seem. This is different from nagging—nagging is bringing up the same issue again and again, without attempting a solution.

4. Spending too much (or too little) time with in-laws. Says Orbuch: “Closeness to in-laws was different depending on whether or not you were looking at the wife or the husband.” Husbands who felt it was important to stay close to in-laws were 20 percent more likely to stay together over time. The opposite was true for women. While Orbuch isn’t exactly sure why this trend emerged, she speculates that it was important for women to see that men prioritized family, while they themselves were often sensitive to in-laws’ advice or commentary on their parenting.

To find out the key advice divorced couples want to pass on to others, listen to the full episode below.