Will Regina Lasko Stay with David Letterman?

An $2 million blackmail plot allegedly masterminded by Robert Halderman led David Letterman to shock fans with an on-air confession that he had sex with women who work for him, making the Late Show host's personal life a hot topic.

He's known as extremely private, even reclusive, but what little is known about David Letterman's love life has always been both idiosyncratic and messy.

A People source says Letterman's affairs, including an alleged liaison with former assistant Stephanie Birkitt, "pre-existed his marriage" to Regina Lasko.

Dave married Regina Lasko last March, and Letterman will be working hard to make sure he makes it to next March as he heads on vacation next week.

Lasko, 48, dated Letterman, 62, for 20 years-plus and is the mother of his 5-year-old son, Harry. She never speaks to press and is rarely photographed.

David Letterman and Regina Lasko got married earlier this year.

She is "wonderfully nice" but "long-suffering because of the length of time Letterman dated her but wouldn't marry her," says a longtime Late Show insider.

"She was crazy about him, so she put up with the situation."

Yet David Letterman was always drawn to other smart, funny women as well, including Holly Hester, but more recently and more significantly, Birkitt.

"Stephanie is sweet, goofy and quirky, which is a major lure for David," says the source, who has discussed both Lasko and Stephanie Birkitt with Letterman. "She's a peculiar character and David is fascinated with peculiar women."

Still, another source close to the TV host says, if forced to make a choice, Letterman will opt to do whatever he can to shore up his marriage.

"The truth is," says the source, "he's 24-7 focused on his wife and son."