Emotionally Preserved?

I find myself wandering around the house with music blaring in my ears but not actually listening to it.  I have other things on my mind today.  Although this may sound like the ramblings of a depressed person, I'm far from that.  I'm merely thinking about thinking.  What's the term for that?  Metacognition!  Yep, I looked it up.  Ok ok so getting to the point of this post- I was thinking about that underlying feeling that even though you're surrounded by people who know you and love you, there's always this feeling of being alone.  Maybe I am the only one who feels that way or maybe it's some kind of self preserving tactic my brain has conjured up so I have the ability to make it through any kind of loss being emotionally intact.  I feel like I'm walking parallel with those around me instead of together.  It doesn't bother me at all.  It's just a feeling that pops into my head from time to time that I find sort of odd.