I've always formed really close relationships with coworkers, I always get greeted by a few of them with a huge hug and I've talked about a lot of different aspects of life with them, yet it never really gets to the point where we actually hang out outside of work.
This so describes my workplace. I have never before worked with such unprofessional people. I have nothing to do with my co-workers outside of work and as little as possible to do with them at work.
I'm close with everyone in my small office. I don't hang out with them on the weekends or anything though, because everyone else here has kids and I do not...no one else here really does anything on the weekend besides doing stuff with their kids. My bf and I are always going somewhere on weekends anyway, so I'm fine with things the way they are.
I get together with a few occasionally. We'll have lunch or go to happy hour to celebrate birthdays and stuff, but there are only 1 or 2 I'd consider good friends.