There are few things more painful than the feeling of resentment. It has been described as "drinking poison and then waiting for the other person to die." When we are caught in resentment, we poison our own well. We are the ones who are suffering. And it is for ourselves, as much as for the other person, that we must work to forgive.
Sometimes people will tell us we "just need to let go"-- but this is easier said than done.
All three of the basic Artist's Way tools facilitate forgiveness. Morning Pages helps us to see our own part. Artist Dates fill our personal well and keep us from feeling victimized. Walking helps us to let go as we move from the mental into the physical, freeing ourselves. Used all together, the tools are marvelous medicine.