Honestly, as a no-kidding honest suggestion, I would suggest reading Carmilla and bits of Dracula, seeing as they're kind of the pinnacle of Vampire fiction, for better and worse.
Anytime someone has trouble with a gothic idea for fiction, I point them to the classics. You don't need to bust out Victorian writing chops, but examine how authors deal with the concept of breaking out of personal chains of behavior (which was the effect Dracula in particular had on those he turned), and the duality between the masks people wear to seem decent versus the unchained Id of the vampire characters. You don't have to restrict yourself to analyzing gothic vampire literature, but that is the most prevalent and easy to find example of the genre today.