Energy is returned. They'll repay your mistreatment. They'll punish you.
They distrust. One misstep can break their trust after a long period. Things will change forever.
If you mistreat them, they'll talk. They'll tell everyone. Your actions will be known, and no one will respect you again.
They may forgive but never forget. If you harm them, they will always bring it up. You will always remember what you did to them.
High standards. They'll leave if you're unworthy. They'll find someone trustworthy.
They think rationally. No matter how much they like you, if you hurt them, they will cut you out. They'll leave without another chance.
They'll be disappointed, but not yelling. Because they would never have done the same to you, they will make you feel guilty.
They're vengeful. If you betray them, they will seek revenge. They won't stop until you repent.