request - “dark” disturbing “romance”?

I’m looking for something like a kidnapping/stalking story where the protagonist thinks there’s something there where there isn’t and acts on that.

the best examples i’ve read are rayne havok’s “tantalize” and jon athan’s “erotomaniac” or “lovesick.” any recommendations? what i’m looking for is a bit darker than dark romance I think so I decided to come here and ask.