Living At Home

I am 21. A junior in college. A waitress. And I live at home.
It has become part of my identity. Gross.

It wasn't so bad when I was younger. I was actually best friends with my mom, but when I turned 15 I made a decision that would effect my living situation for many years to follow. I decided to be a foreign exchange student. When I returned home from my year abroad. I was more worldly, more mature, and more willing to yell at everyone. I had entered my teenage angst years at 17.... I've been living at home ever since then. With the exception of 9 months living with my friend and then going on Eurospring, but now I'm back home with my parents. I am 21. We fight and fight and fight. Then have a laugh. Then fight and fight and fight. Now, I know that they always will me with provide food, constant bitching, and a warm place to shit, shave, and sleep... They even seem happy, sometimes, to do so, however,
at what age is it inappropriate to live at home?

My living situation is starting to feel a little awkward, but between work and school there is 'seemingly' no way around the financial aspect... except of course credit cards....
and *bitch bitch bitch bitch bitch