This occurred a day or so after installing the newest video drivers. Not knowing if that was the cause, I rolled them back to the version I thought worked last week, but the problem persisted. The only Mod I've installed was the Nebula one, which I thought I only had to remove the cfg file and the Nebula folder in the cache folder. I will try deleting the main-user.cfg, cache and config folder later tonight. Thank you.
CPU: AMD FX-8350 8 core processor 4GHz / GPU: GeForce GT 730 @ 1920x1080, 60Hz with 1GB adapter RAM / RAM: Patriot Signature 4GB 1600MHz 240-Pin DDR3 (only 2GB work, don't buy it) / Motherboard: MSI 970 Gaming MS-7693