I have another one from TS4! Mine wasn't an in-game horrifying moment but I was making my real life house and family. Everything looked exactly like the real thing and I worked so hard to get everything done. I had just saved the house to my library when the game crashed. I couldn't watch as I exited the game and opened up the game again. Everything - and I mean everything - had gone. All of my saved households, lots, and rooms had all been lost forever. That included all my first sims and first houses. I got so mad that I made an incredibly ugly sim and gave her a really bad house. This was my 2nd horrifying moment in TS4.