Memorial Day: How Should We Remember Those Who Fought for the Bad Guys?

How should we remember those who fought for the bad guys on Memorial Day?

U.S. Grant describing his feelings at Appomatox Courthouse:

I had known General Lee in the old army... but did not suppose... he would remember me.... When I had left camp that morning I... was in rough garb... without a sword... a soldier's blouse for a coat.... I found General Lee.... What General Lee's feelings were I do not know. As he was a man of much dignity with an impassible face, it was impossible...