I am going to jump in here with my perspective on this, especially this helpful "orange and apple analogy (or simile, i didn't take english lit) :)
I too have mostly felt different from other people but not known why. Some of it was my interests were different from people around me, maturity levels were different, and other traits that make people interesting and themselves.
But one thing i've noticed in the last few months is that when I'm feeling "centered" or content (i.e. the panic and anxiety is temporarily parked away) and i am relating to others, I can often reflect after and say that we had an exchange where we were both the same (maybe both oranges for example, in that we 'got' each other and had a good time convversing). When I am not consumed or distracted by anxiety, worry and rumination, I am a good person: I am funny (i think), open, understanding, interested in what others say, helpful and sociable. Others who are in that 'zone' relate back to me in that way and we have a nice time of it together. Whether this is a 1 minute interaction at the grocery store with teh clerk, or a nice evening out with a few people at a craft meeting. My mood definitely determines whether I'll be able to relate or connect to others who are feeling content or not. If i am having anxious thoughts, ruminating, starting to feel anxious about how others are percieving me or what i'm saying, then I don't tend to come home and feel i've had good connections. In a group of say 10 women at a craft meeting, a couple will be in a content mood (or else why would they come) and a few will be maybe a bit tired or frazzled and a few may be really distracted by their own inner self talk and feeling agitated that their needs are not being met. How I experience my nigth with such a group depends pretty much completely on what mood and attitude I have and level of mindfulness I bring to the table so to speak.
There have been entire years where I've been agitated and anxious the entire time while out with people and no wonder I didn't hit it off with anyone during those times really, except for other dysfunctional or codependent people. I am starting to really see this now. When I'm calm, I more easily "see" the people around me who are feeling anxious themselves, and I (codependent) used to try to rush in to help them (not a good tactic until i have more skills). I am starting to breathe through it and let people feel what they feel instead of trying to rescue them from their own inner struggles when I was not invited in to do so.
Without getting preachy I just wanted to pipe in and say, sometimes people are just not available for us to engage with despite our desire to do so, despite having things in common with them, despite maybe even their desire to do so. I will try to remember my own advice here as I work through my own fear of rejection. Interpreted one way, i see an apple as a content person. Some days I feel like an apple and the world is an apple orchard, other days, not so much. I spent several years being deeply suspicious of people who seemed balanced and content most of the time. I thought it was an act. perhaps for some people it is, but i think there are people who really are content and balanced. I laugh when i think back to one friend i had briefly who called me "her together friend". She 'bought' the show i put on around her. she had no idea what was really going on behind the curtain. i of course had no idea of any of this at the time, that was over 10 years ago.
If that makes any sense...
I don't know if this matches up much with what Davit was originally alluding to with the apple and orange images ,but our different interpretations are what make these concepts richer in the end i think.