Oh! Bryony, so that's a whole genre you're not able to read?
I can't read really, really bad horror books, like some that are written these days, same as can't watch some really scary TV shows.
But I do like the horror classics, by Edgar Alan Poe especially, Mary Shelley, & Robert Louis Stevenson. But I wouldn't read Stephen King.
IMO, some of Shakespeare's plays are 'horror stories', 'Titus Andronicus' definitely.
The 'traditional' tragedies' are pretty horrendous, in each, their own way, methinks!
Oh, actually I have read those classics - Some Poe, which I liked, Frankenstein and Dracula and Jeckyl/Hyde- I liked the story, but not the style of writing. I was thinking more modern horror than monster horror.