Forgiveness

What does the Torah, speaking on behalf of the creator of morals and ethics, have to say about this? If G‑d were confronted, so to speak, with this complex moral query, how would He respond?

But we don't need to take an "all or nothing" approach. If restoring the relationship is impossible it is not always necessary to terminate all contact or become antagonistic...

How do you know when you have been forgiven? Or does the guilt just go on and on?