Here is the thing about being loyal to an employer. I don't think it is the way it used to be. There is no loyalty from the employer to the nurse so why should I be loyal to my employer?
I was told that I would have an extensive orientation, that I would have regular meetings to discuss progress and would have 4-6 patients. I was lied to. My "extensive" orientation was about 5 weeks total, 3 of which I was basically left to fend for myself while my preceptor did her homework for her BSN classes. I did not have regular meetings to discuss my progress, I had one meeting at the end of orientation. And 4-6 patients? Please. I routinely have anywhere from 5-8 patients....yes, some shifts I have six but I often have 7-8.
So no. I, personally, do not have any loyalty to my employer. Also, my unit has hired a bunch of new graduates after me, mainly because no one but the "I need an RN job to pay my rent" variety would last on my unit...and even they are dwindling.
My unit did not "do me a favor" by training me. The work conditions are such that they cannot attract anyone but new gradues to work there.
I understand why preceptors lose interest in training new graduates, but perhaps places need to start looking at WHY they are unable to keep people and WHY there is such a high turnover. Some of it may be because newer nurses don't have the same loyalty as their once was, but sometimes it may just be that it is a terrible place to work.
In the case of the OP, even if your current job isn't terrible I say go for your dream job. Your employer does not give a rat's a** about your career . What you owe your employer is to be at your scheduled shifts on time, for the duration of your shifts, and to do your absolute best for your patients and coworkers during the shifts, and the required amount of notice while quitting as per your company policy. Beyond that, you owe them nothing and believe me, they don't feel for you either!