With the price of divorce running anywhere from about $1500 into the kajillions depending on your economic status, it makes sense that people might try harder to keep their marriages together, or just live separately without formalizing anything. I actually know a couple whose mediator advised them that they didn't have enough money to go forward with their divorce. The wife's boyfriend was none too happy about that, and when the husband found out that there was a boyfriend, they wrangled the funding to make their split legal.
But not only are people too broke to break up, they're also apparently too busted to keep a gumar on the side--rich guys like Tiger Woods being the exception--as infidelity rates also continue to fall:
Among adults who were ever married in the 2000s, 21% of men and 14% of women reported that they had ever had sex with someone other than their spouse while they were married, according to the Project's analysis of General Social Survey data. In the 1990s, 22% of ever-married men and 14% of ever-married women said they'd had an affair.
For those who are married currently in the 2000s, 16% of men and 10% of women said they had an affair while married. In the previous decade, 16% of men and 11% of women said they'd cheated. The number of women who said that infidelity was "always wrong" increased to 84% in the 2000s, up from 73% in the 1970s. Some 78% of men in the 2000s said infidelity was wrong, compared with 63% in the 1970s.
That people still intoxicated by the Summer of Love's lingering vapors might be more inclined to step out than those who came of age through the viral 80s and 90s, and on into the herpetic aughts, isn't exactly surprising, but nor does it necessarily have anything to do with economics. Fucking around was a lot more appealing when the worst thing you could catch were cooties that were easily cured with a course of antibiotics.