Next time let her go sleep quick or talk in the mirror until the mood changes. As soon as the sim gets the mood pause the game fast - don't wait for them to get any automatic actions queued up. Pause and let them go sleep or use the mirror. If it's hysterical, let them calm self down, if it's mortified or very sad or enraged, I think it's give self a pep talk. As for getting back the sim, just exit the game without saving. Not to the neighbourhood - exit to the main menu or exit the game itself. If you already saved well try to load a previous save from the main menu.