For years after I started working (when I was first out of college), I felt like I was very guarded at work. I felt like I couldn't reveal too much of my personality for fear of it being used against me somehow. I also felt like I shouldn't make any friends with my coworkers; I felt like if I let someone that I work with in too close then it would come back to haunt me somehow.
I really shouldn't have worried about it so much. Although there haven't been that many people I have wanted to stay in touch with long after employers have changed, I have made acquaintances (maybe even friends) with many co-workers over the years.
Having these relationships at work are very beneficial for many reasons. Being able to talk to someone else in your situation at work is helpful to sort out issues or problems you might be having. Seeing things from someone else's perspective is always helpful. Also, having someone else to talk to is a great way to relieve stress. You don't have to be venting about a problem to vent stress. Just connecting with someone else and presumably getting away from your desk is a stress-reliever in itself.
Do you have any relationships like this in your current job? If not, it's so easy to get started. Is there anyone at work that you felt like you've gotten along really well with? Do you find yourself talking to someone for more than just a few minutes in the break room? There may be a good relationship hiding there. If it's appropriate, ask that person if they'd like to grab lunch one day. This is also helpful if you find yourself talking a little too long with them in their office (i.e. their boss sits next to them and they need to get back to work).
