Ask HN: Building Relationships and Growing Network

During my 6 years in the industry, I never bothered making new connections or growing my network. To be honest I wasn't aware of how important connections are for personal and career development. Apart from networking, I didn't even make new friends during this time and I am stuck with just a few friends. I sometimes feel very alone when I can't find someone to hang out with during weekend.

Those who sit all day long working on a computer, how did you manage to make new connection and grow you network? Also how do you make good friends online?