Can you keep a secret?

SO, my boss told me a secret, and I'm pretty upset about it. One of the girls at work is going to get fired, but that is not going to happen until I get back from my vacation in two weeks. I was told this because my boss has been working with the girl on a project and getting her up to speed on certain things at the office, but it is just not clicking, and my boss wants me to take over/not waste her [boss's] time with this girl since she is going to be let go.

I am upset about this because I like this girl. She is sweet, great with the patients, and reliable. I will agree, that she is too "blonde" sometimes, and in the past few weeks had made a few significant/bonehead errors. I know that she is nervous and anxious about these errors, as well as her job security in general, especially since we recently rehired a girl who quit last year to work closer to home.

I am upset because I have ranted before about how bored I am at work now that there are three assistants, and how I had wanted to use the fact that there were only two of us as reason to ask for a raise but then I felt like I couldn't since we hired a third, but I definitely did not want this to be the outcome.

In the end, we all agree that the girl is kind and sweet and reliable, and good with the patients, but certain....necessities, with the computer charting and things like that are just never going to click. And it sucks that in this day and age, the it comes down to some one losing her job because she doesn't excel at learning the technology.

I am also upset because I really don't want to work with Heather again. I feel taken advantage of, time-wise. She is also kind of a mega-cunt 85% of the time.

I get into this mode where I am SUPER loyal to my job, even though it might not be in my best interest. Yes, I can look for another job, most likely get one closer to home. I still debating going to school for dental hygiene. While I do love being an assistant, I am waaaaay to skilled to make $30K. Also, if I was a hygienist, I wouldn't have to play office politics. I would work out of my own room and be accountable for my own patients/charting/instruments/etc.

Fuuuuuck.

All day I have been helping this girl extra with little hints and whatnot in hopes that maybe she can turn things around. If it does happen, though, I hope I'm not there when in does. I'm probably going to cry, too.