What is a friend?

Is a friend someone you've known for years?

Someone you went to school with,

who listened while you wallowed in a pit of tears,

while deep inside they held something more.

Someone whom you've come to know everything about,

Devouring them so their secrets shared are out,

exposing them for the world to see,

or at least threatening to,

Or do they devour you?

And after betrayel however signifigant it may be

you hide away so the world may no longer see

your flaws, imperfections,guilt, insecurities.

As if you knew what it meant to feel secure,

you just put on a mask and walk through another door,

brushing off every puncturing eye,but their impressions stay.

So you put on another layer of skin and look away,

And when you've gotten to where you're alone,

thoughts falling back towards home,

you drift to way back when,

and you wonder if you could still notice a friend,

or even define one, after running around eeping

all you have left to yourself, you still feel a lonely need, 

to trust someone, let them in, into your castle,

which you've built brick by brick,

with walls so they'd be thick

enough to keep them out,

the eyes of peers, strangers, and even kin,

but how do you know when it's time to let someone in?

How do you identify a friend?