The number one cause of divorce is problems with communication. While a person might think the issue is intimacy, money, or commitment, the cause of these issues is a couple's inability to properly communicate their feelings and concerns about these issues. Other common causes of divorce include infidelity, violence, and addiction. There are usually reasons cited that was the final straw that broke the marriage, such as an affair, but the root of that reason might be a lack of intimacy or communication between the couple. Of course, there are some couples who simply fall out of love or who married too young.