I wouldn't say antisocial, but I'm not out to be anyones friend, I let friendships happen without actively trying. I don't connect with a lot of people so I just remain quiet instead of forcing myself through small talk I have no interest in. I don't like being fake and don't care about how a random persons day is going. Normally it takes me awhile to get to the point where I'm more talkative and open, once I get to know someone well enough I do care what they have to say. Also, being very introverted, I tend to like only having a few close friends and hang out one on one or in small groups.
Joining the military has helped me break through most of my social anxiety but put me in a place where I do not fit in. I get "your very quiet" or "you need a personality" a lot, but it doesn't bug me. I take pride in speaking when it matter and not being a loud mouth, and my personality comes out to friends only because it's misunderstood a lot.
I guess you call it antisocial, but I can enjoy a meaningful conversation with anyone, it's just small talk and get to know someone parts I don't like.