All relationships have their ups and downs, and life can certainly deal out its share of challenges. But keeping things fun—and having fun together—is what keeps couples strong through good and bad times... and the effects are instant and obvious. 

What to do: Watching a comedy, playing practical jokes, or just keeping things playful between the two of you will make all the difference. Every time you do something that makes you or your partner smile, it drives a physical change and allows your body to release chemicals like dopamine and oxytocin (sometimes called the “cuddle hormone") in both of your brains. You'll feel happier and closer.