Pain is pain, joy is joy - you can't avoid bringing pieces of yourself into a role.
I ultimately have faith though, that good films will find their audience.
I've done almost 20 films and I still worry about not finding the next one.
Actors are such an insecure breed.
The first thing I do when I read a part is see if I can identify emotionally with a character. If I make that connection, everything else is just working on knowing their life circumstances and manifesting those through practice and research.
In horror, character development is often pushed aside in favor of the shock value. The best genre movies to me are movies like The Shining. You had a connection to the characters in that film.