You have to recognize your capacity for harm. You cannot omit the harm you've done to others to remain "good." Anybody can be a bigot. Anyone can be an abuser. Anyone can harm anyone at any time even those who have been harmed themselves. The world is not made up of victims and villains only, this is life, not a Saturday morning cartoon and you are a human being who can or maybe even has hurt others and you HAVE to acknowledge that to learn to be better.
This is the panel that finally convinced me to read Dungeon Meshi. It's the only comic I've ever seen that gets crying right - it's awkward and uncomfortable, it's not remotely photogenic, there are way too many fluids involved.