Character becomes strong when doing right requires less internal debate.

Internal debate is where good intentions get lost. Every argument is an opening for a reason why this case is different, and there is always a reason. When the right response arrives without negotiation, you are not more virtuous, you are simply not giving the negotiation a chance to happen.

Notice the situations where you find yourself arguing with yourself repeatedly. Make a standing rule for those, decided once. Then the recurring debate stops being available.