I think this will only work if you have been able to see wraiths before with a flashlight, and now cant.
In order to fix this and keep your game at high quality settings you must
Open Steam
Go into Library
Right Click Garry's Mod
GO into Properties
Click on Set Launch Options
Copy and Paste this into it
-autoconfig-xres=1920-yres=1080
Trust me it should work if you were able to see wraiths before.
Good Luck