In-Game Menu Fades To Black

So I've been running the game relatively problem free until today. When I press Esc to bring up the in game menu, I see the menu for a split second before the screen turns black and I'm unable to click anything. If I'm fast enough, I can click one of the options, but thus far only Save will allow me to see the menu.

I'm unable to change my graphics settings to fix this as I can't access the options menu. I'm using an NVIDIA 660 graphics card which until now has been running the game perfectly and my computer meets all of the recommended requirements. The only change I've made recently is I've added a second monitor to my desktop setup, however I tried playing the game with the second monitor disconnected and it's still not working.

Any help is appreciated. No, I have no mods installed and no customizations to the game whatsoever.