Happiness was achieved by being part of their society as a couple
It has been traditionally expected that two people will date and eventually marry if the relationship works out. Modern couples have taken a long look at marriage. Many of them believe it is an institution that has outlived its time. They see marriage less of a guarantee of long term commitment. To these couples, marriage is nothing more than a dangerous trap that allows people to relax too much.
Traditional marriages have often been relationships where two people have ended up despising each other. Because society expected them to stay together no matter what happened, they did so. Their happiness was not personal. Happiness was achieved by being part of their society as a couple. Modern couples believe happiness is attained only with hard work, and that being married robs a relationship of this effort. They would rather defy tradition and keep their relationship on an informal basis.
When a marriage does not work for the people involved, many of them choose to divorce and move on past the experience. Some of them will marry again, but others will remain single. [...]
When people get divorced, they often go through a series of dates that result in physical intimacy. These people are not really seeking a partner. [...]
Some people spend years in an unhappy marriage because they are terrified they won’t be capable of finding a new partner. [...]
Although many couples have eschewed marriage, they still want to live together. This is fine as long as the relationship goes well. [...]