I had never seen Eraserhead before. In case you haven't seen it, let me summarize the parts I remember for you:

There's this guy who's terrified of everything, but particularly women. His hobbies include watching the lightbulbs burn, listening to the radiator, fantasizing about strange women, and not sleeping. So he gets a girlfriend. Her mother is a monster who asks him if he had sexual intercourse with his daughter. He dreams or has visions of wormlike, spermlike creatures that infest everything. He gets his girl pregnant and she gives birth to a monster – this time, a bona fide monster. So he has to get married. And then things get worse.