With high-profile affairs like former New York governor Eliot Spitzer being caught with a hooker, the cause often appears to be lust. But not with Sanford.
He claimed in his confession last week he actually fell in love with his mistress.
But what does that mean for his marriage to Jenny Sanford?
Marriage, family and child therapist Dr. Jenn Berman, author of "The A to Z Guide to Raising Happy, Confident Kids," discussed the differences in Sanford's affair and what it means for his relationship with his wife on The Early Show Monday.
After reading e-mail correspondence, Berman concluded Sanford certainly believes he is in love.
Rodriguez asked Berman if the Sanfords' marriage can survive -- like the Spitzers -- even though the relationship between the governor and the Argentine woman seems to be love rather than just lust.
"It's much more difficult for a marriage to survive an emotional affair," Berman said. "With Spitzer, he was just having sex with a prostitute. I mean, not just, obviously, he betrayed his wife."
"But in this situation, this is an ongoing affair," she said. "And when you have a sexual indiscretion, or a fling, it's a moment of poor judgment, but when you have a one-year relationship that involves emotional attachment and connection, it's a series of lies and deceit, and that's much more difficult for a marriage to recover from."
Rodriguez asked Berman about Sanford's claim that he wanted to go to Argentina to break off the affair.
Berman said that probably wasn't Sanford's intention. "We don't go to Argentina to call things off," she said. "We go to Argentina to have physical contact with people in Argentina."
Berman said she doesn't buy the fact that he wanted to end the affair.
"That's what phones and e-mail are for," Berman said, referring to a way he could have broken off the relationship. And referring to his lengthy love letters to his mistress, she added, "He clearly knows how to use e-mail."
Berman said the affair must be incredibly embarrassing for Jenny Sanford.
Berman said Jenny must be feeling anger, as well as experiencing issues with trust. She added Jenny must also be worrying about her family.
"This couple has a lot of work ahead of them," Berman said.
Berman said "it's a tough call" to know whether or not the couple will stay together.
She said, "(Jenny) is clearly is very committed to her marriage and her husband, but this is a tough one to work past."