knee Deep in Design

I'm the sole designer for a print broker. Sole, as in the only one here that can do what I do. This also means that sick days are poo poo'd, vacations will come every 5 years, all responsibility falls onto me, and who really needs a lunch break. I've got work building up around me to the point where I can't even remember what i'm supposed to do. I won't remember your little logo to design when I have 4 16+page publications to design and layout. The only problem here is that my employers are a bit fickle, not about who they hire, they've hired dozens of people in my 2 years here, it's more like they hire people who can at least dress themselves, but once they hire this person, they start to pick them apart. Let's just say, I made my boss mad one day, and I was taking messages from people responding to the designer position which was about to become available. They like me though (Lexapro is my savior, who's yours?) but being burned like that, I have become very territorial of my position here, I reign supreme in my little office that I was awarded. They have suggested getting another designer in here to pick up the scraps that fall off of my table so to speak, but to me that means that my job will be replaced by someone willing to work for less than I do (hard to imagine), and come with rechargable batteries as they will have to be a robot.