Once-trusted Clinton advisor George Stephanopoulos writes in his new memoir that as soon as he heard the President’s denials of an affair with Monica Lewinsky, “I knew in my gut that Clinton was lying.” Stephanopoulos’ long-awaited tome “All Too Human,” all 456 pages of it, finally hits book stores this week — ironically, only one week after Andrew Morton’s Lewinsky tell-all “Monica’s Story” entered the marketplace. What readers will find in George’s book is a harsh portrait of Mr. Clinton — and an even tougher one of the First Lady. Hillary Rodham Clinton is depicted as having been so stressed out over Whitewater that she cried and at one point, in 1994, accused Stephanopoulos of having been less than loyal: “You never believed in us.” Stephanopoulos, 38, who now lives in New York, received a $2.85 million advance for his book and these days is a commentator on ABC.