Nice post about friendship and expanding it to include human relations.
Indian Vedic philosophy has many stories about friendships are over 5000 years old.Relationships between Sudama and Krishna , Duryodhana & Karna, Drupad and Drona in recent times of Gora & Badal of Chittorgarh and are very much in alignment with Greek Philosophy.
Coming to the understanding of Relationships as Human beings I would like to add a few pointers.
All things present on the planet have a fixed behaviour pattern which they follow. That helps them discharge the expectations other entities have from them. All Matter, all plants and all animals behave in a uniform way and get easily identified.
Human beings are different in the sense that they have a virtual presence that is not just the matter. That virtual part of them is driven by desire, thoughts and wants which need to be fulfilled along with the needs of food, shelter, sleep and sex.
Relationships helps satiate the needs of that virtual entity which we all can understand but can not see, feel, smell or touch. Every Human being universally had this need and relationship alone can help him fulfill the needs. Human beings remain empty without the same.
As you have written on this beautiful topic request you to give more insights into how Human being can behave as expected of a human being and at the same time create beautiful relationships.
Look forward to read more on this from you,