Here is exactly what I did to solve it:
The latest Update 5 for Maya 2018 is here, bringing significant stability improvements and bug fixes. If you've been experiencing crashes or installation hangs, here is what you need to know. ✨ Key Fixes & Improvements
Resolved several "Unexpected Termination" errors when closing scenes or switching viewports.
Many UI glitches can be solved by renaming your maya/2018 folder to 2018_old to force a fresh preferences reset. 💡 Pro-Tip for Beginners