Apparently Graham understood how you feel (from an article in a magazine Graham started):

When Watergate came to light, [Graham] was blindsided. He had held Nixon in such high regard for so many years that it was difficult for him to reconcile the character of the man he knew with that of the man heard on the tapes.

“Never, in all the times I was with him, did he use language even close to that,” wrote Graham. “I felt physically sick and went into the seclusion of my study at the back of the house. Inwardly, I felt torn apart.”

“There was a side of Nixon that my father had never seen, and that concerned him,” Franklin Graham explained. “He wondered if he had gotten too close to Nixon, and maybe stepped out of a role he should have really stayed in.”

The President had not confided in him about his mounting troubles. After the full story broke, he all but blocked the evangelist’s access to him during the rest of his presidency.

“I wanted to believe the best about him for as long as I could,” Billy Graham wrote. “When the worst came out, it was nearly unbearable for me.”