What it takes for someone to heal another person's broken, black heart that doesn't beat (psychologically, not physically)
-Patience and time. A lot of it. It must be consistent, constant. No gaps.
-Care. Be there for that broken person whenever he/she needs it.
-The ability to stand up to that broken person, little by little, when he/she is strong enough, and tell that broken person that he/she is wrong or needs to do better.