I used to be more concerned

Has anyone ever noticed the odd man out? The lonely boyfriend/girlfriend sitting in the corner because their significant other isn't involving them. Or, the new friend someone brought along that nobody knows. Depending on the person, I could feel their discomfort. I could see that they didn't want to impose on some inside joke, or personal conversation. It's a difficult position to play. If I was a familiar of the group, I'd usually make some sort of effort to involve them. I mean, I couldn't be bothering them right? They came to have fun I'm pretty sure. Regardless, I was always concerned about everyone having a good time. I didn't want to leave anyone out. Now, I've begun to hang around a group of people who I don't know too well. We've all hung out several times, but it's obvious that they're closer. The reason I'm around these people is my girlfriend. They're all usually pretty nice, but as for that consciousness of another's discomfort, nobody notices. My girlfriend usually leaves my side and doesn't want me clinging to her. This goes on for usually the whole night. I wonder what happened to me. I guess its just this group of people that I can't connect with. I try to engage in group conversations, but I'm so self conscious of what to say. I hate that I've become that guy. I don't want to be, but its difficult when everyone seems so uninviting and not having my girlfriend kind of be my gateway to engaging her friends. My biggest fear is that I come off as annoying, so keeping quiet usually seems the best solution unless I'm approached. Maybe one day I'll be able to get back to that point where I was comfortable enough to make the newcomers feel welcome.