wexxam Can you load a new save? Please try for comparison's sake. Please also try loading a different household within the original save. You can choose Load Game rather than Resume. I'm not saying you need to abandon your save or sims, only that this is useful information.
If only your main household is affected, please go into Documents > Electronic Arts > The Sims 4 and delete any lastexception files you find. Try again to load that household, and see whether you get a new LE. If you do, please attach it to a reply here. You'll need to delete the file's first line in order to upload it.
If you can't load into any household, please provide a dxdiag. Hit Windows key-R, enter dxdiag in the run box, wait for the scan to finish, click "Save all information," and save the file to your desktop. From there, you can attach it to a reply using the camera (Insert Media) icon included with the other formatting buttons.