"Bill Clinton fooled around with Monica Lewinsky," Santagati said. "Now, no offense to Monica, but she, she's no Jessica Alba. She is ... the intern. She's the last person in the world Bill Clinton should have any sexual contact with. And that makes it extremely provocative."
But it's not just people who cheat. Dr. Judith Eve Lipton, a psychiatrist, said that a common myth is that many animals are monogamous. She and her husband, David Barash, a zoologist, who co-wrote the book "The Myth of Monogamy," say there are a lot of misconceptions about monogamy.
For instance, many people grow up believing black swans, wolves and elephants are happy, monogamous mates. But scientists now know that "virtually no animals practice sexual exclusivity. They keep house together year after year in many cases, but they're sexually promiscuous," Lipton said.
Barash notes that the film "March of the Penguins" was touted as a great peon to lifelong monogamy, but "the truth is, these animals ... remain monogamous, faithful to one partner, for one breeding season. The next breeding season they will choose a different partner."
Scientists used to believe many bird species were monogamous, but recently, they've found otherwise.
"The female birds go off in the bushes and have sex with somebody other than the guy who's sitting on the nest," Lipton explained.
Scientists around the world have tested the DNA of baby birds and found even those in the same nest had different fathers. All that is evidence, Barash believes, that monogamy does not come naturally.
"When it comes to human beings, there's absolutely no question about monogamy being natural. It's not," Barash said. Barash and Lipton believe it all goes back to evolution: The male's goal is to make sure his genes live on and therefore he sets out to fertilize as many females as possible.
"Sexual opportunity is the name of the game for males," Lipton said. Women, on the other hand, spend nine months pregnant, then have to care for their children. So it's in the interest of the woman to find one man who will stay with her, or at least help her take care of her offspring, and some might argue that man is preferably wealthy or powerful.
"Females, by nature, are more choosy and less opportunistic," Lipton said.
But of course women cheat, too, Santagati reminds us.
"Men cheat because we are ... programmed to cheat. But who are we cheating with? We're cheating with women. I've cheated before. I've been a cheater. I know that these women are in on it. Women have been cheating on their boyfriends to be with me at times," Santagati said.
But according to Barash, we shouldn't lose all hope in monogamy. There are a few animal species that are sexually faithful. Like the Malagasy giant jumping rat, the fat-tailed lemur and the California mouse. "You have to dig pretty deep to find other species that are … truly and reliably monogamous," he said.
"We're less like a Malagasy giant jumping rat than we are like ... chimps and ... gorillas and our primate ancestors who are not monogamous," Lipton said.
With so much cheating going on, Santagati tells people that they should "not go and think that you need to get married, have two kids, and live happily ever after. That, my friend, is a load of crap for 90 percent of the population."
So are most men who get married making a mistake?