I can 110% relate to this. People have no idea that we are the complete opposite of snobby or stuck-up. I am just very insecure and apprehensive. I have become more comfortable in my own skin which has led me to "appear" more confident. You just have to get out there and do it. Nothing is going to change unless we change ourselves. Usually I have no interest in what my co-workers are talking about, but I usually try to say something just so I wont appear to be detached, withdrawn, aloof, etc.
My co-workers probably think that I don't like them, but that is not at all the case. I am just quiet and I don't think that I am better than anyone. If anything, most times I have felt inferior to others thus leading me to be withdrawn. It has gotten better over time but it definitely has been a struggle. Again, we just have to put ourselves out there. Sometimes, if you appear to be confident, then it actually turns into real confidence. I am just tired of crying and being angry at myself for my lack of social interaction and relationships. At 25, I have to be more proactive and try to make things better myself instead of just waiting for something to happen.