I'd like to offer a different interpretation on this. I'm not going to back it up with Bible verses, you can do the legwork yourself if you want to pursue the issue further:
What is forgiveness?
I'd say it is liberating someone from the the 'debt' of whatever offence they committed against you.
When should I forgive?
(Here we depart from the 'folk orthodox' position)
The question needs to be rephrased to "when can I forgive?".
And the answer is: when the offender has asked for forgiveness, and "brought forth fruits worthy of repentance". Forgiveness is a transaction between the offender and the victim; you can't perform that transaction with just one person at the table.
Note that we're talking big, soul-destroying offences here, not "he looked at me funny on Sunday morning". (Longanimity is not a word we use much, but Christians could do with learnin' up on it).
How should I forgive?
There are basically three cases. The first two pose no problem; it's the last one we may disagree on:
- Offence occurs, offender realises, asks forgiveness, makes reparation, you forgive*
- Offence occurs, offender oblivious, you approach them, offender realises, asks forgiveness, makes reparation, you forgive*
- Offence occurs, offender oblivious, you approach them, offender ignores you or worse: denies everything, blames you, etc.
What can you do in the third case? You can't forgive, but you don't want to carry the worry of that unpaid debt around with you all the time.
You need a professional debt collector. Hand him all the paperwork, and get on with your life. Like Jesus: "He committed Himself to Him who judges righteously".
This is where we make the distinction between 'forgiving' and 'letting go': find someone you can trust, tell them (or write them a letter) about the offence, tell them about the consequences, perform some symbolic act (burn the letter), pray, let it go*.
*I.e. your work starts here...
How can I forgive?!
The message of the Gospel is clear: as offence calls for repentance, repentance calls for forgiveness. There's no wriggle room.
But that doesn't mean instant forgiveness (which risks being as empty and meaningless as a flippant "sorry!"), nor does it mean that the offender has a "right" to be forgiven. There is nothing more perverse than turning a victim into an offender because of their 'unreadiness' to forgive (even more so if there is no repentance).
There are verses (forgive as you have been forgiven) which I believe can become more than trite platitudes, if you let them in. But ultimately, if you are in this situation, there's not much some guy pontificating on a website can do for you. You need a flesh-and-blood someone to see you through, someone you can trust to shut up and listen, to understand, to encourage.
That person may not be your pastor/priest.
What about reconciliation?
It seems obvious that in the case where the offender refuses to recognise the offence, reconciliation is impossible. But what about in the other cases? Should you forgive and forget? Can you forgive and forget?
I don't see how you could literally forget. What you can do is cease to ruminate - but that takes time. 'Letting go' is a first step, but there will probably be many lettings go.
As for real reconciliation, that will depend on many factors. I don't see how it can be considered an obligation: if trust has been betrayed, it can't just be turned back on. Whatever happens, I'd say that it is impossible for the relationship to go back to what it was before (if there was a relationship before), and again, it will take time.
All of this takes time, but time is standing still until you can forgive, or let go.
Finally
If you are reacting against this 'redefinition' of forgiveness, you may feel more comfortable calling my letting go 'forgiveness', and my forgiveness 'reconciliation'.
Some associated (googled) reading