I know exactly how you feel! I am the same way. Soul mate! Haha. Anyways I just really saw myself in your post. There's a couple of things you have that I have. For one, I am very defensive. It seems like you may be the same way. Which leads me to the second thing, you feel the need to explain yourself too much. Which the defensiveness and the explaining CAN go hand-in-hand. Though it doesn't always, of course. I've always had these problems and I too have the problem where no one gets me. Also, when I try to explain things to people they either think I am picking a fight or I am trying to prove them wrong. Which isn't the case.

My thing is I want people to know why I think the way I do, or if I made a mistake, why I made the mistake I did. Normally if I do something wrong I did it because of a way I was told, wasn't told, or something of that nature. I have a Supervisor much like yours who doesn't want to hear it, but I still tell him. I don't mind if he gets mad at me (not much he can do anyways, he has to go through the School District to get rid of me) and I just like my Supervisor to know that everything I do has an explanation for it. Same goes with friends, family, my animals (just kidding, lol) but you know things of that sort.

The good news is you aren't the only one! Here's the bad news.. There is no cure! We were blessed with this and we will always have it, haha. Unless we tell ourselves to shut up, or duct tape our mouth (super glue might work better actually..) then we will always have this problem. We just have to deal with it, and so do the people around us. Take care mate.