Try resetting your user files as described in the factory reset described in this post: http://answers.ea.com/t5/The-Sims-4/FAQ-Troubleshooting-Steps-amp-Known-Issues/m-p/3621199
You won't loose anything. Just make sure to not delete any files and make a backup.
After renaming, repair your game by clicking on the dots in EA app.
Try on a new game with nothing added back first (start new game). If it works, put back your save game and try again. If it still works, you can start putting stuff back.
The rest does not need putting back, cause they are mostly cache files that recreate or log files that are not needed for the game.
im having an issue where Milestones are only applying to one sim in the household and not the other sim. For example, starting first romantic relationship and falling in love only appleid to one sim i made and not the other sim i made. Even after they both had their first woohoo only one sim got the milestone for it
