Recently, as I walked to meet a good friend for lunch in New York, I noticed myself feeling unusually relaxed and peaceful. About halfway into our lunch my friend said, "You know, you seem more relaxed than usual." He read my body language well.
It is an observation that draws upon a historical data set, as "relaxed" is a relative term. It made sense: I've known him for seven years. I do not have many close friends who I have known for more than 4-5 years.
Later the next night, at a burrito place, he mentioned I always order steak or pork when I select a meat option in restaurants. This is true. I ate so much chicken growing up that I never order it as my meat of choice. Meanwhile, I noticed he was wearing a new shirt, and we both noticed our mutual friend of seven years was wearing new shoes.
These are trivial examples, but the point is this: noticing slight changes in a person's behavior, appearance, or state-of-mind requires knowing the person well and over a long period of time.
And it is very satisfying to feel known and noticed.
Time. It heals all wounds, wounds all heels, and more than anything else drives intimacy in relationships.