1. You show contempt for each other.
According to the Gottman Institute, where pioneering psychologists Dr. John and Julie Gottman spent nearly 40 years studying marriage, showing contempt is by far the strongest predictor that a relationship is about to end. More than just your choice of insults, contempt can be conveyed by rolling your eyes at your partner, showing disdain in the tone of your voice and mocking their concerns—any of which are enough to shake your partner’s confidence and their very sense of self. Putting it simply, the loss of mutual respect is a nearly insurmountable obstacle in any relationship.