Titane
Ex-Machina
Cape Fear (the original starring Robert Mitchum)
These are the few that actually made me feel uncomfortable. I'm slowly learning to appreciate horror, but nonsense ghost stuff or pointless slashers don't work for me, although The Texas Chainsaw Massacre is a masterpiece.
Shiva Baby is the movie that I consider the most unnerving, but it's billed as a comedy, though it's widely reviewed and rated as a horror, especially if you have social anxiety.
I guess I'm something of a ne'er do well.
Pittsburgh