When David is shamed by Naval he prepares to fight, but Naval’s wife Avigayil (Abigail) calms him down and reasons with him. Ten days later Naval dies of natural causes (alcohol poisoning is implied,) and David marries Avigayil. The text also says that he marries Achinoam, the same name as the wife of his now bitter enemy, Shaul (Saul.) Coincidence? It seems to imply that, by marrying the guy’s wife, he has completely defeated him (both Naval and Shaul.)
Personally, I think that David just realized that Avigayil had calmed him down, reasoned with him, and prevented him from doing something he would later come to regret. All characteristics of a good wife, like mine!