Yes, and I see this especially when the injustice is very grave, such as the murder of one’s family member. The anger can be so intense that the person refuses to forgive for this particular issue. This does not mean that the person is closed to forgiving all other people for other kinds of injustices. At the same time, a refusal to forgive today is not necessarily a person’s final word on the matter. In time, this person may decide to try forgiveness.
For additional information, see: Forgiveness Defined.