Forgiveness is like faith. You cannot will yourself to have it, nor should others demand it of you. You don't "have to" forgive. But you may never heal if you don't.

Society gives second chances because it cannot operate under a rule that doesn't. That's not forgiveness. That's a recognition that there but for the grace of God (or moral luck, if you're not a believer) go we or our kids. Society is not concerned about protecting the kid from the kid's mistakes; it is concerned about protecting itself from its own.

Some childhood "mistakes" are special; they evidence incurable sociopathy and should not be overlooked. But the hypothesis here is that we are dealing with an adolescent frontal lobe, not a birth defect. Knowing the damage done by sexual assault - girls like sex, too, right? - is very much a matter of maturity, whether or not the victim bears any scars.