Over the years I've learned that when it comes to co-workers that's exactly where I keep them, as co-workers, office acquaintances. I don't share personal things going on in my life or that have gone on in my life, only general things.
Part of my experience in learning to be a good listener was learning not to talk so much about me, but instead, ask questions about them? And try and keep the conversation about them and little about me.
When I first meet someone the last thing I want to hear is their life story! Friendships take time to build, time to learn about each others lives. Just like how dating should be!