Lincoln and Ann Rutledge

[Gene C]

That, along with the fact no one outside New Salem ever heard of this great romance, and he never discussed this allegedly key relationship ever, with anyone except for the disputed conversation with Isaac Cogdal in 1860, strikes me as very unusual.

Perhaps he did not want to bring up a bitter sweet memory? It's not an uncommon reaction - especially since many people who knew Lincoln, mention how little he talks about his personal life. (including Herndon)
Up to this time, three of the four most important women in his life have died early in life.