Circle of Trust

From a lot of time I believed that every human being has some kind of a circle (or maybe a sphere) around him that separates him from other humans. This circle (or sphere) starts to shrink with another human as long as his relation with that person becomes friendlier.
So if you can notice yourself when you are introduced to other people, at first you try to keen the maximum space between you and him, as your relation gets stronger with him, the physical distance between you and him just shrinks. If anybody tries to break the borders of this circle, you just get nervous, so if you had ever noticed people in the elevator, as the space is so little, everybody just acts weird, like you see somebody looking at his watch, another just looking at the ceiling … .
The other day I was introduced to someone, I don’t know about his mentality, but every time he talks to me he gets (physically) closer, I just try to get away, and a long loop of this just starts to happen, after a little while I was very annoyed so I told him that his breath is killing me (it’s just to let him keep some space). In the end of the day I apologized for what happened and explained to him everything, for some reason I don’t understand I felt that he was more offended by what I say more than when I told him that breath thing. Can anybody explain?