James Buchanan. Our 15th President. He was engaged to Ann Caroline Coleman. She passed away, which people speculated was a suicide over the engagement that she broke off days before her death. He never married and he never had children.
His fiancée's death struck Buchanan a terrible blow. In a letter to her father, which was returned to him unopened, Buchanan wrote "It is now no time for explanation, but the time will come when you will discover that she, as well as I, have been much abused. God forgive the authors of it [...] . I may sustain the shock of her death, but I feel that happiness has fled from me forever." The Coleman family became bitter towards Buchanan and denied him a place at Ann's funeral.
While I was looking for a dead President to feature for this, I never thought that this random pick would have such a tragic story to it. I bet every Presidents story has some sort of romance saga tied to it. Don't you think? Have they ever made a movie from this story? I would see this movie.
*Believe it or not, History was always my favorite subject and one of the few classes I never failed in High School. There's your History lesson for the day.