Answer:
I can be simple or I can be complex. I can be found in this riddle or in everyday life. I can be shapes or even colors.
I get wet when drying. I get dirty when wiping.
If I have it I don't share it. If I share it I don't have it. What is it?
I am the beginning of eternity the end of time and space the beginning of every end the end of every place.
I can go through glass without breaking it.
Black we are and much admired. Many seek us if they are tired. We tire the horse, and comfort man, and turn White when we've fulfilled your plan.