I work full time. I am busy but like my job and like my colleagues. I get on well with everyone AFAIK. I have five precious lunch hours a week. I spend them food shopping, banking, doing home admin, and once or twice a week I go for a swim - my treat.
So, I am too busy to meet up with people as a rule and go for a drink in the pub or lunch. I do go if I am invited (just a few times a year). I don't send friendly texts to colleagues either as I have never really got to grips with texting.
I realise I am in a minority - nearly all my colleagues both male and female (some childless, some with children) do make time to have lunch with others both inside and outside our department (I work in the public sector). I can see friendships being developed. I never bother to make that leap from colleague to friend.
I realise I must be missing out on some office gossip and don't get to hear as much about my colleauge's home lives. I don't put much effort into social networking, though am always friendly when invited to group gathering and like to talk to people when we're working together. No one seems to think I am anti social and everyone knows I have two children and a busy home life.
As our jobs are in the public sector, any internal job advertising/interviews etc follow clear rules and the process is meant to be quite transparent, so IMO there is little reason to network like mad, purely for promotion reasons.
But I think I am in a minority where I work and wondered if I was missing something?