We have been conditioned by our society that forgiveness means letting the other person off the hook for whatever they did. Given this belief, it makes sense that we wouldn’t be willing to let go of the resentment we have developed towards the other.
Consider this definition for forgiveness:
I am releasing my resentment while not condoning the behavior of the other.
The resentment we hold onto is what kills us, not them. Wanting to be truly free and healthy, it would be wise to forgive and be clear that forgiveness has little, if anything, to do with the other.