The New York Times has a really interesting opinion piece about the downside of premarital cohabitation. Namely, that people living together before they get married tend to "slide" into commitment rather than marking it with a ceremony or declaration, which means they’re more likely to "slide" out of marriage too …
More from the Times article by Meg Jay:
When researchers ask cohabitors these questions, partners often havedifferent, unspoken—even unconscious—agendas. Women are more likelyto view cohabitation as a step toward marriage, while men are morelikely to see it as a way to test a relationship or postpone commitment, and this gender asymmetry is associated with negative interactions andlower levels of commitment even after the relationship progresses tomarriage. One thing men and women do agree on, however, is that theirstandards for a live-in partner are lower than they are for a spouse.
Sliding into cohabitation wouldn’t be a problem if sliding out were aseasy. But it isn’t. Too often, young adults enter into what they imagine will be low-cost, low-risk living situations only to find themselvesunable to get out months, even years, later. It’s like signing up for acredit card with 0 percent interest. At the end of 12 months when theinterest goes up to 23 percent you feel stuck because your balance istoo high to pay off. In fact, cohabitation can be exactly like that. Inbehavioral economics, it’s called consumer lock-in.