I recommend Leomund's Tiny Hut. It's a 3rd level ritual cast spell for bards and wizards that lasts 8 hours. Among other things, it's description include this:
Creatures and objects within the dome when you cast this spell can move through it freely. All other creatures and objects are barred from passing through it. Spells and other magical effects can't extend through the dome or be cast through it.
As long as the hag isn't within the dome's area when the spell is cast, you should have no issue getting an uninterrupted long rest.