In their book Mistakes Were Made (But Not By Me), social psychologists Carol Tavris and Elliot Aronson describe how a fixation on our own righteousness can choke the life out of love. They write:

The vast majority of couples who drift apart do so slowly, over time, in a snowballing pattern of blame and self-justification. Each partner focuses on what the other one is doing wrong, while justifying his or her own preferences, attitudes, and ways of doing things. … From our standpoint, therefore, misunderstandings, conflicts, personality differences, and even angry quarrels are not the assassins of love; self-justification is.