Go out a purchase a length of plastic carpet runner/protector that will cover the couch and place it nobby side up on the couch. She has simply learned the couch is a comfy place to sleep, if made uncomfortable she will not be interested in sleeping there.

As others have mentioned a crate should not be used as punishment, you want the crate to be seen by your dog as a safe have, physical punishment is another no-no in my book, it can make dogs fearful of hand movement and can lead to snapping in fear, using a firm voice not yelling can be effective if the dog chooses to ignore than you can use a squirt bottle with water along with the verbal correction eventualy the dog learns to respond to your voice without the need to be squirted.