I'm usually on my own. Years ago I worked a job where coworkers remarked months into it that they thought I couldn't speak because they had never heard me talk. (It was in the kitchen of a nursing home cleaning the dishroom when I was in college, so it didn't require much communication anyway.) I was just more focused on the work and figured if people wanted to talk to me, they would... Once people started talking to me, I made some lifelong friends there. I guess what I'm trying to say as that personally, I'm OK on my own. When I was a kid in school, I had my own little clique of friends, but I never thought it was exclusive. We let anyone in... even the muslim girl in gym class who looked terrified after 9/11... we were friendly to the dorks. We were only a step above the dorks in the social order anyway, haha! (Ah school days..)
I work from home, and every now and then, we have team meetings. I surprise myself with how social I can be, then... offering tips and assistance and inviting people out to lunch afterward. I have noticed this about myself: If I am around someone who is new or shy, I tend to become like an ENFP and am very gregarious and welcoming and trying to make people feel comfortable and involved. But if people are OK doing their own thing and aren't really interested in me, then I just keep to myself.