Answer:
Though I am dark Adam married me.
I never was but always will be. No one ever saw me but everyone knows I exist. I give people the motivation to better themselves every day. What am I?
I am a kind of coat that can only be put on when wet.
You are my brother, but I am not your brother. Who am I?
Tear me off and scratch my head what once red is now black.
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.