The 19th century Haktav v'Hakabbalah (Rabbi Yaakov Tzvi ben Gamliel) offers a list of daily life ways to enact this mitzvah. He goes beyond treasured friends to include all others with whom we interact. His list includes:
- Affection for others should be real not feigned
- Always treat others with respect
- Always seek the best for others
- Give others the benefit of the doubt
- Do not consider yourself better than others
(cited in Artscroll "The Chumash" (Nosson Scherman, ed) p 662.)
He seems to be teaching that the essence of this mitzvah is framing our consideration of others in terms of respect, care, and generosity, then acting on that framework. That lesson resonates with the popular story called "The Rabbi's Gift." The setting and tone of this story belie the fact that its earliest source was (only) 1979. There are a number of versions; here is my adaptation based on Francis Dorff's original.