I believe that Lee fought FOR Virginia and her sovereignty, he was heartbroken to fight against the United States.
I agree. Everything I've ever read about the man says the same thing. He was against secession, but his loyalty to Virginia forced him to fight for her. It must have tormented him to have to make the decision that he made, but he felt that he had no choice. It probably seems strange to people that a man whose father was a Revolutionary War hero could fight against the Union that his father helped to establish, but I don't think we can understand the loyalty that men had for their home states at that time.