The same thing happened with my game, I made sure my all my mods were updated - but I removed them prior to loading the game after the update. My played households would not load - but the unplayed households were fine. I did more research and found someone say if you use custom food cc, there may be a plate stuck somewhere on the lot that would prohibit the lot to load. So I put my mods back in the game - and it worked! I was able to load my households again. So if you use custom food cc - place them back in your mods folder and reload the game. Hopefully that will work.