Unofficially together

Usually I don't pay attention to something as petty as a title. But we have been dating for almost 6 months. We aren't boyfriend & girlfriend but we do couple things. Everyone looks at us as a couple. But we never made it official. I'm ok with that except for when he jokes about talking to other girls by saying "technically we aren't even together". I don't know if I should worried or if I'm just over reacting.