Do you have any idea what's happening *after* the chapter you're stuck on? Sometimes skipping ahead and then coming back to fill in the hole can get the ol' muse started up again.
I have trouble working that way, but it works for many!
Playing stuff in my head works for me. If I get really stuck, I'll go for a long walk and rehash and rehash a scene or scrap of dialog until it starts working.
I 'play' the story in my head all the time... even when dreaming... but when I sit down to add what I've thought of or dreamt of, it doesn't seem to gel with the main plot, and I get really frustrated.
It's not like I'm trying to write the Great American Novel... far from it. It's just another horror story.
Sometimes skipping ahead and then coming back to fill in the hole can get the ol' muse started up again.