Wedding season is upon us, even on TV, where an awful lot of season finales seem to include weddings.

On television, as increasingly in real life, marriage and the public commitment one to another that it entails is rarely considered the prerequisite for sexual intimacy between a man and woman. I can’t recall the last time I saw a TV wedding that didn’t assume the happy couple was not only sexually active, but living together prior to marriage.

It’s not popular to bring this up, but sexual morality precludes any form of sex outside of the marriage bond. As Rev. Michael Sheehan, Bishop of Santa Fe, recently put it in a letter to his priests about the pastoral care of cohabiting couples: “when it comes to sexual union, there are only two lifestyles acceptable to Jesus Christ for His disciples: a single life of chastity, or the union of man and woman in the Sacrament of Matrimony. There is no “third way” possible for a Christian.”

In spite of this, an increasing number of couples, including Catholic couples, choose to live together without the bond of matrimony. What’s sad is that living together before marriage is widely thought to be a good preparation for marriage, when in fact, setting the matter of sexual morality aside,  it’s been shown over and over again that cohabitation is extremely detrimental to marriage.

People who live together before marriage are close to 50% more likely to divorce once they marry. The longer they cohabit before marrying, the more likely the marriage will fail, and the more times they have lived with others, the less likely they will succeed at marriage.

Why should that be so? It seems logical to assume that a couple who managed to stick together for a long time before marriage could make it work afterwards. It’s reasonable to think a person who has lived with different people at different times might have a better sense of what he or she is looking for in a spouse.

Alas, no. It seems that living together without benefit of marriage may create one or more mental habits that make forming a marital bond more difficult. Resources available at foryourmarriage.org point out:

•    Only half of cohabiting couples ever marry.

•    Living together often creates an unhealthy dynamic where one partner is reluctant to marry and the other is hoping marriage will eventually result. There is a tendency on the part of the “weaker” partner to avoid real issues in the relationship to keep it together.

•    Alternatively, couples who live together because they “aren’t ready for marriage” often develop a “low commitment/high autonomy” dynamic. That means they may be so independent by habit that the transition to the truly committed marital relationship is difficult and slow, if it ever takes place.

•    Children in cohabiting relationships are at risk. They are more likely to be abused, and after five years, 50% of cohabiting couples have split up, as compared with 15% of married couples.

In spite of the surprising amount of evidence against cohabitation as a relationship-builder, people persist in believing it will help.

I’ve been involved in preparing couples for matrimony for some 15 years. When I started, cohabiting couples were less common, and those who made that choice at least knew they were defying Church teaching and were making a free decision.

Today it’s far more common for almost every couple who comes to us to be living together — and completely ignorant that there’s a problem. No one has ever told them that it’s harmful to both their souls and their relationship to do so.

They haven’t heard it in Church, and no parent, grandparent or teacher in a Catholic school has ever mentioned it. When we lay out Church teaching on marriage and sexuality in its fullness, it’s not uncommon for them to be both struck by the beauty of Church teaching and to feel profoundly cheated that they had never heard it before.

If we want our kids to get married and for those marriages to be successful, we have to remember to teach them that living together before marriage is wrong.