What is Friendship?

It is sharing
both big and little things,
joy and sorrow,
laughter and tears.
It is counting on another
to understand your mood-swings,
to put up with your failures,
to be there when needed most.
With a word of encouragement,
a smile, a look...
How do I know what Friendship is?
I know because you are my best friend,
and in our friendship,
all these things are found.