We are called to extend love even to those who do not seem to deserve it. Resisting evil without using evil is a dilemma for the Christian. But it is the most powerful agent of healing. And in the case of people who have suffered abuse part of the healing process for them may be finding a way to forgive. Those words affirm that it is through forgiving others that we find forgiveness.
Modern psychology understands that same thing.
We are not in a position to accept forgiveness, to forgive ourselves, if we cannot offer it. Hate is corrosive. It damages us. Love on the other hand brings about healing. One becomes less and less given to hating as one becomes more and more given to loving.