Ive battled with this. I have great social skills, most of the time.
But theres a line. Private life, happy life.
There can become a point in a job where people get too personal. I really don't like that "we are a family" BS at work. They aren't my family, they are my co-workers. And sometimes the questions they ask me can be a little out of line. I don't want to discuss mine or your sex life at work, and no I really don't care what you do after work or on the weekends, and please don't ask me everyday what I'm doing. Also, please stop trying to show me pictures on your facebook or phone of your kids, I ain't got time for that in the middle of my shift.
I always acknowledge my peers, I welcome everyone who I come across in the work place with a smile and hello, I ask how they are doing. But other than that, lets discuss work and be efficient. I don't want to sit there and get behind in my work talking about things I'd rather talk to my husband, friends, or family about.
However, it has challenged some of my work-place relationships because my co-workers can become very close to each other, like best friends, and I can be considered to be more of the "quiet, standoffish" type.
I feel like it really shouldn't be that way. It makes it so uncomfortable at work when your co-workers are best friends and you're there trying to get your job done so you can go home on time to your loved ones.