How do you forgive those who wrong others?

when others hurt me I can manage to forgive them by trying my best to love them as if I were to love my own children. But when I see people being victimized by other people I would feel very sad and very angry, I want to make this pain go away by forgiving them just like the way how I forgive those who wronged me. But I cannot do it because I feel that those who have done unjust to others deserves to receives equal love as those who had been victimized by them. I am just not capable of unconditional love and also I dont want to even try to love those who hurt others. So even though you can forgive those who wronged you, how do you forgive those who wrong others?