2nd Degree Relations

There is an old Israeli-army quote about career-NCOs: "I want a large circle of 360 degrees, and inside a small circle of 180 degrees!"
It is used in great reverence for their intelligence (where is that sarcastic blue when you need it) but I use it symbolize tight circles of relationships. Inside, you have your closest friends. Friends you can share any thoughts with. People you can share your very life with. A circle so tight it does seem to have only 180 degrees in it.
Outside, there is the "friends of friends". People who, usually, are met through mutual friends, who you keep a friendly term with, but not a person you would normally call out of the blue for nothing. These are the second degree relations. People who are not really close, but close enough that you don't want to hurt their feelings. Usually because of repercussion from people you do care about, but never mind the motive.
The worst is when these people don't notice. The circles are often very clear, and people share definition of a circle. It is rare, although it happens, that one person might place another in an inner circle, while the latter places the former in an outer circle. This misunderstanding of relationship definition can be, at best uncomfortable, and at worst, downright annoying.
This can often lead to greatly awkward moments.
Like last night
When I found myself in an outer-circle party, when all my inner-circle friends - the link to the hosts - were missing. It was a birthday party as well, so small gifts were involved, on top of everything. One got stuck on a trip with a broken down car and could not make it, one has a pregnant wife who was feeling ill, and another was sick at home with mild pneumonia. All valid excuses, except the pneumonia - what's a little coughing of contagious viruses! Except, that I was mostly by myself with people I wasn't so close to and did not look to get so close to.
And now I've made their inner circle, which is why they are bothering me with IMs all day! Like now, as I'm writing this!

Social civility is a bitch!