Extreme lag and freezing after Patch 2

I had over 100 hours of the game before patch 2, and while my computer was never amazing, I only ever had issues with lag/performance on custom "High" settings in Arlathan.

Ever since Patch 2, I'm getting extreme amounts of lag/performance hits so bad it's completely unplayable. Nothing has changed and lowering my settings isn't even fixing the issue. The entire screen is completely freezing every couple minutes. Even just walking through the Lighthouse with nothing happening is so painful I can barely stand it.