When a Story Is On the Verge of Falling Apart

I've got a short story with all the right elements: a haunted house, a deranged baddie (yet to appear), a woman out for revenge, and a dead daughter who turns up as a ghost, possibly to help her mother.

The only problem is, it refuses to be written. I don't know who the baddie is yet. It certainly isn't the ex-husband; he's too much of a fop. I get only so far with things and then it just crashes. And I'm not sure whether I want to try to beat this one into existence. Damn thing might roll over and die on me. Maybe it already has.

Well, I'll come back to this one later, I guess.