Best Freind

Please define for me,
o; pretty please,
a best friend to me.
Someones who's there till the end?
Someones who's a good friend?
Does everyone have one?
Does anyone really even need one?
Its hard to tell who has my back,
just from who has it long enough to stab it.
If i let someone in,
I have to tear down the walls and reveal all my sins.
They have to swear to secrecy,
If they tell, I just might go crazy.
Who's my best friend?
I'll be by myself in the end.
I don't have one,
Am I ok without one?