Contempt, they have found, is the number one factor that tears couples apart. People who are focused on criticizing their partners miss a whopping 50 percent of positive things their partners are doing and they see negativity when it’s not there. People who give their partner the cold shoulder—deliberately ignoring the partner or responding minimally—damage the relationship by making their partner feel worthless and invisible, as if they’re not there, not valued. And people who treat their partners with contempt and criticize them not only kill the love in the relationship, but they also kill their partner’s ability to fight off viruses and cancers. Being mean is the death knell of relationships.
Kindness, on the other hand, glues couples together. Research independent from theirs has shown that kindness (along with emotional stability) is the most important predictor of satisfaction and stability in a marriage. Kindness makes each partner feel cared for, understood, and validated—feel loved. [link]