Help! My boss is promoting the wrong person

Help! My boss is promoting the wrong person:
Dear Evil HR Lady,
I’m writing because I don’t know how to handle my entitled, know-it-all, gets-away-with-murder coworker. I work in a small office of four people, and I’ve been the HR assistant (doing generalist work) for five years now. The payroll coordinator thinks that, because she has been here the same length of time and has seen what we all do and gets the occasional Society for Human Resources email, she somehow knows everything about HR and is now qualified to be the HR manager. She has a bachelor’s degrees in drama and no experience actually doing HR work — she is a data entry clerk at best, but for some reason my boss is going along with this idea of promoting her. 
She acts like a princess, orders me around like I’m her personal assistant and complains constantly that she is overworked. The thing is that she wouldn’t be “overworked” if she actually showed up on time and didn’t spend so much time socializing. She arrives at least 10-15 minutes late everyday, but my boss never sees it because she doesn’t get here until 9 or 9:30 a.m. and we’re expected to be in at 8:30 a.m. She also doesn’t seem to notice when this woman disappears for a half hour every day to go chat with a coworker next door. 
My question is, aside from getting a new job (which I am looking for), what can I do? Do I bother saying anything to my boss or will I just look like a tattletale? It’s so hard to keep my mouth shut and bring myself to work every day when I have to put up with this craziness. I work hard and have consistently been given duties from my boss of increasing responsibility to help me grow in my career, but it just doesn’t seem worth it anymore.
To read the answer, click here: Help! My boss is promoting the wrong person

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