@SimplyJen
igzor is right. My computer is I mac but I'm running the sims 3 on windows 10, bootcamp. Usually, I'm not in the circumstance that playing the sims 3 over 5 hours continuously. Whenever I have to do some work, I definitely turn the game off even 10 mins away for giving some time to let my computer get rest for a while. My DCCache is around 1 GB, almost store item, and Mods folder is 150 MBs. Usually, I play for 2 hrs in one go. But this time, it happened when I played only 5 mins in real time and 10 hrs in sim time. (just sleeping during the night). I always save my game just before my sims go sleep at night. Yesterday, the game crashed while loading to main menu from the beginning. It showed me the screen is grayed out with no message. I waited for about 10 mins, and then I had to force quit. I think I need to do factory resetting maybe..
@igazor Thanks for the exact answer. I wanted to know what the files mean. :)