Why do you say that I likely will forgive better if I see the “potentiality” for love in the one who hurt me? To be quite honest with you, all I see is narcissism in the one who abruptly walked out on our relationship.
Aristotle makes the important distinction between Actuality (what is occurring now) and Potentiality (what underlies the current situation, including the capacity for greater perfection, even if we never reach true perfection). The one who abandoned you had the potential within to grow as a person, to develop more goodness within that then can be behaviorally demonstrated outwardly to others, including you. The narcissism of the other is a current Actuality. The person is capable of much more with conscious, deliberate effort to bring out a fuller humanity, a deeper sense and expression of love.
How do I “acknowledge the other person’s humanity” when this person acts more like an animal than a person. Sorry for such a negative statement, but this is how this person behaves.
Please keep in mind the distinction between what Aristotle described as each person’s “potentiality” compared with the person’s “actuality” in behaving in accord with the moral virtues. The one you described as acting “like an animal” is not actualizing the potential for high level human behavior. Yet, this person still has the “potentiality” to achieve this, with proper virtues education and encouragement by wise people. As you see this potential, you are acknowledging the humanity in the other person.