True Friend For Life

This is more or less a puzzle, not that hard though:
We have a true friend in life
Always there for us, though never say a word
We never really think of our friend, only in a passing or when we find it amusing and entertaining
Not sure why that is so, but the association of our friend is for things that are gloom and dark, a bit unfair in my opinion.

I wish our friend say just a word, a word of support, encouragement, criticism or anything, I would be grateful :) But hei, the guy is just that kind of friend.

Anyone know who our friend is?? Weird thoughts from walking to work "in the morning"

Here is the answer to your riddle:





Your own shadow! hehehe