I'm glad that ended up working out! Seems the back-up save file finally managed to be useful :)
Please avoid closing the game while its currently saving. This means any time you manually save, any time you enter the main menu, and any time you delete a piece of clothing, or exit out of Outfit. I'm unsure what exactly happened to cause your save file to become corrupted in the first place, but at least avoiding closing the game while it's saving should help!