I am not really sure what is corrupting your game. You could try going to where your saves are located and deleting: All quicksave files (there should be 4) and saveData (numberless), images and the wallpaperSave. The game should start from 0 with your saves intact. However if one of your other saves are corrupting the game then I looks like the only way to make it work is to delete all your save data. I hope this helps 😟