Answer:
I always have to work with something in my eye.
I'm found on Windows yet I am just a decoration. What am I?
A young man wants to have me but when he has me he no longer wants me. Blade in hand he attacks me and does his best to remove me. Yet he knows that it is all in vain.
The more you take away from it the larger it becomes. What is it?
Crooked as a rainbow and slick as a plate, ten thousand horses can't pull me straight. What am I?
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.