Stanley, referring to his and other studies, identifies two types of commitment: dedication and constraint. He writes, "Dedication reflects the desire to be with a person in the future, to form an identity as a couple, to sacrifice for and prioritize the relationship. Dedication can lead you to do the right or best thing for your partner and the relationship, now and into the future. What we call dedication often goes by the simple name of 'commitment' in much of the literature where commitment is measured relatively well." In contrast, constraint consists of past and present factors that make leaving a relationship more difficult and consequential. Financial factors are often examples of this. Stanley states: "While it's become easy to have positive perceptions about the benefits of cohabiting prior to, or instead of, marriage, what people fail to recognize is that cohabiting also increases constraints to remain together before dedication has become clear or matured."
Stanley concludes that unhealthy relationships (which tend more toward aggression) tend to have lower dedication and higher constraints, especially common among couples who cohabitate. So, when considering the concept of cohabitation, ask yourself, "Am I committing to this relationship or avoiding commitment?"