We have all been hurt emotionally and in that process of trying to protect ourselves we can repress emotional responses. A multifaceted approach is a consideration.
Ask the person what makes them laugh, feel peaceful, or happy, or what they like to do. Encourage them to begin the process of healing by giving themselves experiences of success.
Depending on the person's beliefs they may want to consider counseling, movement or dance, energy work, prayer, or meditation. In my experience developing compassion was the most effective means of healing. It began with acceptance, forgiveness and moved into compassion over time, though the steps were part of a process.
Begin with where the person is willing to go, what they are willing to do. Ask God/Source/Creative Forces and his Angels (Raphael) for help and the ability to recognize it when it shows up.
It can be done. Harm done to us can be healed.