Three levels of forgiveness - emotions, drives and obligations. The emotional level consists of your instinctual anger, rage, disappointment, betrayal, confusion or fear. This is about raw raws. The drives consists of your "need" for them to say sorry, make amends, regret their actions, have a conversation or emphasise with you. In other words, it's about needing the situation to turn out a particular way. The obligations are very similar to the drives, except it is about their duty to perform these actions rather than your desire to make it happen.
Someone can forgive all of these levels. Suppose someone says that they are sorry and the other person "there is nothing to forgive". Then perhaps they mean that there was no harm or that they have completely forgiven all levels.
Alternatively, someone might forgive on one-level, but not another. For example, it seems that most of the harm of holding onto a grudge comes from the emotional level and the drives level, but less from the duties level.
Your duties (towards others) may include what you are supposed to do if others don't fulfill their duties (towards you).