Help! My inability to come out is taking its toll on my relationship.

Ok. I really need some help. I am gay (29 years old) and am currently in a relationship that been going on a little over 6 months.I am out to my good straight friends and the majority of my gay friends. I am not out at work (with a few exceptions) and I am not out to my family (besides my brother)My problem is I have issues with bringing it up to people. There are certain people who I can't bring my bf around for fear of "outing" myself to them (including work people). I don't get why I am so afraid of it. None of these people would care and they probably have already figured it out by now but I can't bring myself to do it.For example, I have an event planned that a lot of work people are going to that I'm debating if my bf should come to. He says he doesn't mind not being invited but I feel it isn't fair to him to be 'ashamed' of him. And if I invite him but only under the assumption he keep our relationship on the DL that's also not fair and I know I will be very stressed out about it the whole time.These situations cause me a lot of anxiety to the point where I actually lose sleep over it. What the hell is wrong with me? Should I just introduce him to my work friends? Am I just not cut out to be in a relationship? I just don't know what to do...Any help would be very appreciated...