as we forgive

I cannot believe there are many people who say that line in the Lord's Prayer "as we forgive those who trespass against us...." and never feel at least, a little uneasy about it.
Forgiveness is hard work. God has overflowing vats of forgiveness, grace, it seems, ready to bundle us up into his heart whenever we say sorry. Although this saying sorry can be difficult we are assured it works....what can seem harder is forgiving other people.
Now, whilst it is well within most of our capabilities to let go of every day things, life gets a little more tricky when it comes to things which people have done to us over time, things which have made us less than we are in some way, and then have become almost normative. We have begun to make excuses for the other person, we let things go, or, even we are in such a position of weakness that we have no good or safe way to fight back.
And then there comes a point where we realize and things change in some way. What is happening to us stops but our emotional and spiritual selves are left hurt and angry. It is hard to forgive, it can even be hard to see the other person as a real person, somehow we have to keep going and we push on through.
I was contemplating this very problem and I found myself sitting in front of the thirteenth station of the cross....often a picture of Mary with Jesus laying dead across her knees....a pieta.
At first I had no idea what this had to do with the subject at hand but as I looked at Mary I found myself wondering, how on earth did she move on from there, how did she forgive?
Mary did not have superhuman powers, grace and obedience,yes, but she must have felt so hurt and angry at that moment.
So what pulled her through? What stopped her from holding onto the taunts and hatred which Jesus had endured. Perhaps it was just the joy of the Resurrection. Perhaps her blessedness extended to some super big dollop of grace.
I don't know the answer. I do know that looking at this image I realize the possibility of forgiveness...for real. That somehow, and somewhere God can turn even the most bitter heart from anger and hatred.
This is not a sugar and spice answer, I do not believe that Mary is a sugar and spice character. All it says to me is that we can, somehow, with God's grace forgive even those who have offended us most horribly.