Ahh, Valentine's Day -- a time for romance, flowers, a little chocolate and -- cheating?
It's been around as long as there have been men and women, but you might be surprised, even shocked, to find out just who's doing the cheating now.
The age-old assumption, that it's the man, is showing some cracks.
When you look around these days, on shows like "Desperate Housewives," most of the time, it's not men who are on the prowl.
" 'Desperate Housewives,' for guys, it makes you wonder, you know, it makes you want to think: 'Well, what is she doing when I'm at work?' " one man remarked to Brzezinski.
Fact is, in the infidelity department, women are catching up.
"I think, in the last 10 or 15 years, it's really become a part of many women's lives, a big secret," says Susan Shapiro Barash, a gender studies professor who has interviewed more than 1,000 women about their secret lives.
Her best guess: 60 percent of women will cheat: "If we think about it, a woman today who travels for business is in the same position a man was in the '50s, '60s and early '70s. Where he would put down a credit card, stay at a hotel, and have some fun on the side, well…
"Even if she's the stay-at-home mom," Barash continues, "she can have an affair, if that's what she wishes to do."
So the soccer mom is also the cheating mom?
"She could be," says Barash. "She could meet her lover at the soccer game.
"Women are more independent and more autonomous. And if they're not happy in a marriage, they know they have other choices."
And, while surveys and studies vary wildly as to what percentage of women are having affairs, most seem to confirm that the number is rising.
"There's no question that more and more women are cheating," says Dr. Judith Kuriansky, a psychologist known as Dr. Judy to her radio listeners. "When you look at what the surveys have said, it can be up to half of women have some dalliance or some affair for some amount of time at some point in their relationship. And that's a big number, considering that it was not anywhere near that. And certainly still not as high as the number of men who stray."
Darren Morgenstern is a happily married man who runs ashleymadison.com, a Web site for attached people with cheating on their minds. "When monogamy becomes monotony: That's our trademark slogan," he says. "When people come to our Web site, we don't want them to feel harshly judged, we don't want them to feel ambushed. They've already made that conscious decision, already identified that maybe they are leading lives of quiet desperation."
In Toronto, where The Ashley Madison Agency is based, Morgenstern's been dubbed "the king of infidelity."
His Web site has generated lots of controversy, and lots of interest. In fact, a reality show is in the works.
"Are you facilitating affairs here?" Brzezinski asked.
"It isn't making it easier," Morgenstern answered. "Affairs happen for lots of reasons. You might as well say motels make having an affair easier, escort agencies make affairs easier."
Morgenstern showed Brzezinski just how easy it is to log on and set up a profile -- no names, of course.
"It might take them a minute or two to get back to you, or a second or two to get back to you," Morgenstern says.
"Call me naïve," Brzezinksi says, "but I was stunned" at how easy it truly was.
"So," Brzezinski asked Morgenstern, "(the person who immediately answered Brzezinski's fake inquiry) thinks that – (the person Brzezinski was pretending to be) is looking for an affair?
"No question," Morgenstern says.
"Sarah," not her real name, observed, "You could go through the pictures and pick and choose as if you were ordering, you know, online from Eddie Bauer. It seemed that easy."
Sarah is an attractive woman in her early 30s who answered an online call from Ashley Madison to talk with CBS News. She has a young child at home and a husband she has no intention of leaving.
"I just couldn't believe you could shop for men like you could shop for shoes -- online. Literally."
She knows that if her husband found out, "Well, I think that he would leave me. I think that would be about it. He would just be upset, very disappointed, and I think he would walk away."
"I stopped counting at 15. …It almost got scary," says Carol, also not her real name.
But Carol says her affairs made her feel better about herself: "There's times when you go to bed at night, and he won't touch you and you wonder why. You think there's something wrong with you, and having an affair takes that doubt out of your mind, because there is somebody who finds you attractive. …It's nice. …That makes me feel good, and I don't get that at home, so I've got, I guess, the best of both worlds."
Susan Barash, the gender studies professor, says, "Some women are not willing to leave the marriage and break up the family, and yet they're willing to have the affair and keep it a great secret."
And do they feel guilty? No way, says Barash: "These women, as convention-bound as they are as wives, feel that, as a lover, they're entitled to the experience. Their husband isn't giving them what they need, and this is a conscious choice to get it elsewhere."
Still, as a lot of men already know, the risks are enormous. And the chances of a happy ending?
"The trickiest category of all," Barash observes, "is the love affair. That's when a woman is really OK, her life is fine, she has a good husband, a good marriage, and suddenly she meets a man. Falls head over heels in love with him. That one really creates a lot of problems in a marriage."
"As a psychologist," Dr. Judith Kuriansky says, "I have to say it's really problematic. I have lots of couples, and individual men and women, who are in turmoil now. …I mean, it's really been -- all rules are broken, no holds barred. Gender roles are confusing, and so both men and women are confused. And it does not do well for the family structure that women and mothers are having affairs. So there's a lot of concern, I think, in terms of the solidity of the American family."
What's happening to the institution of the family? Barash asserts that's "the irony. I mean, women want to be married, it's still a pretty riveting goal in our culture. And everyone idealizes marriage. At the same time, we read the tabloids -- what's happening to the movie stars, who was unfaithful -- so there is this mixed message that marriage is forever. But if it isn't, you can always get divorced."
"At the end of the day," Morgenstern says, "the heart wants what the heart wants."
SOME QUICK FACTS from the American Journal of Sociology: