Sounds like you might have some bad/corrupted CC installed. Have you installed new CAS content, custom households or Sims recently?
Try clearing these cache files and see if clearing those out helps. The game will regenerate new ones.
CasPartCache.package: CAS parts that appear in Create-A-Sim
scriptCache.package: Mods
simCompositorCache.package: New Sims, default skins
Try running your Mods folder through
Delphy's Dashboard and check for corrupted files. If you are not familiar with the Dashboard see Nona's
Understanding Mod and CC Conflicts with Delphy's Dashboard guide.
If you install the content via package files you might want to consider moving your mods folder to your desktop or make a new folder on your desktop and move all your CAS content to that folder and add a few back at a time, run the game and see if it works with what you added.
If that fails try putting your Saved Sims folder on your desktop.
If all else fails content installed via 3Pack is a little harder to find but you could try putting the DCCache folder on your desktop and see if you can access the costume makeup. See
Crinrict's Suggestions Here. Mel's Method on that page offers another way to check those files.