Cohabitation by definition is two unmarried people of the opposite-sex living together. It has been called by various terms, such as "living together", "shacking up", "cohabitation", "serial monogamy" or "living in sin." It is a halfway house for people who do not want the degree of personal and social commitment that marriage represents, at least for now (Waite & Gallagher 2000:42). Besides, people believe that living together in a trial marriage tells potential partners something about what marriages would be like. The information gained could help couples make good choices and avoid bad ones. The survey evidence shows how widespread this belief is. The number of unmarried couples has increased dramatically over the past four decades, and the increase is continuing. It is seemed that the cohabitation is replacing marriage as the first living-together experience for young men and women. According to reports only in America, the number of unmarried couples from 1960 to 2002 has increased by over 1100 percent.
It is overwhelmingly clear that cohabitation is very harmful for a number of reasons. In fact, there is not a single good reason to cohabit that stands up under sociological, psychological, health (either emotional or physical) reasons. Cohabitation is so damaging to our human relationships and leaves such deep scars for a lifetime.
The couples who live together before marriage have higher separation and divorce rates. A growing number of young people are cohabiting today, believing that the cohabiting relationship