itch.io

Assuming that you have the most recent version of this mod, my bet would be that you installed the bugfix mod, then uninstalled the bugfix mod when you installed the marriage mod, as that seems to produce the most errors on start. To fix it you will need to either delete your Strive program folder and extract a new copy, or copy the contents of the "backup" folder into the Strive program folder to restore the game to the backup (edit: note that if you use this method the mod system will incorrectly report that you still have mods applied, but that is of no further consequence). The mod system automatically restores the game to this backup state every time you apply a set of mods. So to install mods on top of the Bugfix mod you need to apply it once by itself and then apply it every time after that, otherwise it will be uninstalled.