Forgiveness doesn't always mean that we can put things back together the way they were. The analogy I always like to use is that of physical healing. Reconciliation is like being healed. Sometimes there will be scars. We may have to bear those for the rest of our lives.
Reconciliation is about healing wounds, and forming healthy scars, and learning to live again.
That four-step reconciliation process can be blocked, anywhere along the way. It can be blocked, as I said, when people pretend that something didn't happen, or when they deny any responsibility for what they've done. The process can be totally short-circuited when people just leave, or when the person responsible has died. The process fails when we don't know who our adversary is, or who has offended us or who has been hurt by us. Anonymity and facelessness make it almost impossible for healing to take place.