hmmm try the backup folder method
go to the electronicsart /thesims3/saves in the saves folder find your save you play for example my save is Sunset.sims3 and the back up of it Sunset.sims.backup i copy those folders to the desktop for now and for safe keeping then rename the .backup one rename it to something else
for example test.sims3 launch the game and see if it's ok
if it does launch and all is well at that point i would save a copy of my family to the library and or the lot too just in case you may have to start a new game but you'll have your family and house to place