You are struggling with that which most Christians both admit and don't admit. There is a level of "everyman" failure that we will share with others. But we really don't let others know the reality of our failures, because they are so real as to hurt others, and ourselves, and our relationship with our Lord.
You are very correct, and your words are a reminder that any doctrine which can be misused/used to divert our attention from true holiness, from the true demands of the Lord on our lives, is a doctrine with which we must be very careful.
Jesus does not tell us to "go and do likewise" because he was an extrovert and liked to flap his gums in the wind.
And the source of that holiness is ???? Our self effort? our decision ? our own works?
reflecting, perhaps you would like to hear my personal testimony? Once, long again, my beloved husband and family and I were being injured in a most devastating way by a certain person. I sat at the table with my older brother - who has always helped me in my walk with the Lord - and I asked him how I could go about forgiving this person. The hurt I was feeling was robbing me of love, joy and peace.
His advise to me was to pray for this person all the same good things I pray for my daughter. He said I would not mean it at first, but if I kept it up faithfully, eventually I would.
He was right. It took about six months before I could really "let go" and "let God". But praise God, now, forgiving is as natural as breathing - and oh so very liberating!!! My love, joy and peace are untouchable.