Who was your wife? This seems to be a common problem for people playing on consoles, I've seen, especially when the spouse is a former "vital" character that was previously un-killable. For example, the Companions members, at least of the Circle (Vilkas, Farkas, Aela, etc.) are immune to actual death during their questline, but once it is completed or they are married by the player, that changes. That's unfortunate, there's a simple fix for this on PC. Once you receive your inheritance letter, though, it's entirely possible to remarry. My best guess would be to try hanging out in cities, especially ones related to your marriage like the city where you met your spouse, or where the two of you lived. That might do the trick.