An Unhealthy Relationship...a vent about my job

Yep, I have decided I'm in an unhealthy relationship....with my job. It's like this boy I dated in high school, I knew we weren't meant to be and really not that great together but it was long term and comfortable. It was easy so I stayed and stayed, I put up with the crap until one day it ended. It's the same with my current job. I've been here over 2 years, I know my job very well and do it very well, I should I'm well over qualified. The day I was hired I was told I'd easily be able to move up into Marketing (where I have a degree) in less than a year, but before that year was over the entire Marketing Department was cut to 10% of it's former size and relocated across the country. My current role is not a challenge, I need almost no supervision, I can alter my hours a little here and there. My direct boss is an amazing man without whom I would have run away screaming a long time ago....But I'm wasting my education here. I'm in a dead end job at a company I don't think will be around in another 2 years. Yes, I'm gainfully employed, and I am so thankful to have made it out of the recession with my job intact but everyday here is exhausting mentally. To come here and deal with incompetent and lazy co-workers has worn on me excessively so. Don't get me wrong, clearly I have my lazy moments, I'll admit to them BUT I don't have a quota either.

I guess it's ultimately so hard because I've always had horrible bosses, for the first time I have a really great one and I'm afraid to loose that. Why am I bitching? I guess I'm just trying to pump myself up for the interview I have this afternoon. As much as I hate my job, it is comfortable and my boss is amazing. It will kill a little piece of me to have to leave him, but I know I must do what I must do. This is what is best for me and my family long term and I know bossman will understand. Even though I know I need to take this step I feel a bit lost.