When we think steamy historic romances, our eye turns to Elizabeth Bacon Custer and her husband George Armstrong, who was court martialed on charges of abandoning his duties to visit his beloved, whom, after her husband’s death, spent the remainder of her life spinning webs of heroism at Little Bighorn. There’s also Jimmy Carter, whose devotion to Rosalynn is legendary – they’ve been married 73 years – notwithstanding his 1976 admission to Playboy that he had committed adultery in his heart. Good thing we now have a better role model in the White House. But what about Abraham Lincoln and his wife, Mary Todd? It is not a relationship known to have been particularly spicy, with more ink spilled over her depressions, and his, than their passion. Learn the truth this summer on walking tours organized by the Abraham Lincoln Presidential Library and Museum that began this week. The free tours of Springfi eld addresses where the Lincolns loved and courted and lived start at 10 a.m. at the ALPLM every Tuesday and Thursday through Aug. 7. Dubbed “Abe and Mary: Quite Contrary,” the walks are intended to help show how a man and woman of different upbringings and social classes came together and persevered.