We always forgive, entirely. As much as we forgive, we are forgiven. So we must forgive everything, especially the very worst things, and the things done that bother us most. This does not mean we do not oppose those things from happening, but it does mean we forgive.
The difference in forgiveness between God and man is a matter of authority… So God can demand greater forgiveness of us than He practices, because He is the judge, jury, and executioner. He is the authority. And His justice is tough stuff, as tough as can be. Hell is that, unending horror.
Forgiveness comes from knowing absolutely deeply in our hearts, ‘There but for the grace of God go I.’ If not for God’s intervention, you would be as bad as the person you have trouble forgiving – or worse. Know it don’t force God to teach it to you through falls more the necessary.
Forgiveness does not mean that there won’t be punishment to the person you forgive, everything is punished somehow, in fact you might even have to be the one to mete it out – but you must forgive nevertheless the person.
Forgiveness means detachment, and means loving the neighbor as oneself in other words wishing all the good in the world, salvation and God for this person and all the joy that brings.
Forgiveness doesn’t mean loving the evil the person does, or the evil parts of the person itself. No one loves that, not even God.
Forgiveness… is interior freedom for a person from the anger and anxiety and other debilitating emotions that come from witnessing evil that is not just punished by God but -will- be part of the Last Judgement you can believe that, as will -all- of your evils as well. Revealed. Before all mankind.
So forgive and forget as much as is wise and prudent to and live a free life, trusting in God to take care of it all. Weep for the sins of mankind and do not hold them in your heart with retribution but with mercy. For now is the time of mercy, the future is the time of justice.