Similar to the friend zone, but when the girl considers you such a good friend that you're like a brother to her. Or a father. Whatever. You can get so close to this girl that sleeping in the same bed is a non-event, because it's just like sharing the bed with a sibling.

when you're hungover as shit after a spending a night drunk as a skunk

When a girl you friend with/crush. Loves you but only like a family. Like a brother, father, cousin, uncle, or maybe her dog. Hey, dog can be a part of the family too. Unofficially
You can get really close to her but you will be considered as a non-dating option. Ok there's a chance you will be on the dating option but the chance are smaller, deal with it.

Similar to the friendzone

Like me, just stuck into the familyzone because I'm fat, bald, and a dude ;_; (Well not really because of that)

When you're not just in the friend zone, but you've been come the brother or sister they never had.

The family zone is similar to the friend zone in that it puts you in a position where a partner isn't interested in romantic interaction because of your role in their life. Being in the family zone means that the person doesn't want to sleep with you because you are a blood relative (like a brother or a daughter).