Forgiveness versus Justice
We must forgive unconditionally. This is actually one of the commands, I think, that is for our own good as well as for the good of others and God's glory. If I don't forgive, my resentment has a hold on me, and my desire not only for justice but for revenge, and since we usually can't get adequate revenge, and often can't get adequate justice, that leads to bitterness.
What is much tougher is the matter of justice. I should forgive the man who molests my child--- though that is difficult, and I probably wouldn't be able to--- but that doesn't mean I shouldn't press charges. I should want him to be deterred from molesting other children. That is one reason why we have public prosecutors, who will prosecute even if the victim doesn't want to. (It isn't just that the victim is biased; the judge and jury are enough to deal with that, since the prosecutor, public or private, just provides the evidence and reasoning but not the conclusion).
If it's an actual crime, then it's easy to let the police and prosecutor deal with it, and the duty of the victim is to forgive personally while at the same time cooperating with the police. Usually it's not a crime. Then it gets difficult. Maybe there will be no justice unless the victim "prosecutes". That is the hardest case, because it is much harder to forgive if you are having to publicize and think about the offense and identify the perpetrator and suggest his punishment. It is much better if someone else does it-- even a friend, but ideally a stranger who is doing it out of pure desire for justice, not revenge, or even better, an enemy who is not unhappy to see your pain but desires justice for you anyway.
For this reason, I think we all should be looking out for people who have been treated unjustly, so we can lift the burden of justice from them and take it on ourselves.