In a letter to Warren "Cubby" Culbertson, who at the time was running a series of religious counseling sessions for couples at the governor's mansion, the two-term Republican explained he was trying to head off a potential divorce from his wife, Jenny.
The message was obtained by The Associated Press through a public records request. Sanford's affair became public in June, when he confessed it after disappearing on a secret trip to Argentina. He had told his staff he was hiking the Appalachian Trail.
"I simply beg for the chance to figure it ought (sic) privately, please beg her for just the first month after the kids get out of school and if I cant get this done then there will be plenty of time for public humiliation and showing the world I am the guy in the wrong," Sanford wrote.
The governor worked on the letter on his state computer May 20, several weeks before Jenny Sanford moved with their four sons to the family's coastal home.
Culbertson confirmed Thursday that he received the letter but did not comment further. Sanford's spokesman, Joel Sawyer, said its contents should not be any surprise because the governor has spoken extensively about his personal life, including in several hours of interviews with The Associated Press.
"It's a deeply personal letter and the governor has made no secret of the fact that he's working very hard to try to repair his marriage," Sawyer said.
The letter sheds light on the relationship between the governor and his wife in the five months between when she learned of his yearlong affair from a letter to his mistress he had kept in his files and the rest of the world found out.
Sanford and his wife have said they are trying to reconcile and the governor intends to stay in office. They are traveling in Europe with their four sons one of three trips they have taken together since the governor confessed his affair publicly. Sawyer said they are expected to return next week.
In the note to Culbertson, Sanford refers to a "present entanglement" in his life and says his wife "grows more and more frustrated with my heart not being right and says simply that I am not trying."
The governor does say he can feel his heart changing.
"The one part where my heart at this point is not where I wish it was is with Jenny. She is a great girl, great mom, great wife and best friend and I am committed to her in a commitment sense, but my heart is just not alive here as it ought to be," he writes.
"I told her the other day I want to run toward her not for the boys, or to avoid repercussion, but because my heart was right. I have got to get his figured out and am committed to doing so. Keep praying for me on this one."