COLUMBIA, S.C. – After going AWOL for seven days, Gov. Mark Sanford admitted Wednesday that he had secretly flown to Argentina to visit a woman with whom he was having an affair. Wiping away tears, he apologized to his family and gave up a national Republican Party post, but was silent on whether he would resign. "I've been unfaithful to my wife," he said in a news conference in which the 49-year-old governor ruminated on God's law, moral absolutes and following one's heart. He said he spent the last five days "crying in Argentina." Sanford, who in recent months had been mentioned as a possible presidential candidate in 2012, said he would resign as head of the Republican Governors Association. By leaving the country without formally transferring power, critics said he neglected his gubernatorial authority and put the state at risk. It wasn't clear how his staff could reach him in an emergency.