回复：How to deal with the boss you can't trust anymore,

If you work for a big corporation, promotion is usually not under control of your boss. There are a lot of factors in promotions: budget, business needs, performance, etc. From my own experience, business need is most important and performance is less importance. Of course, you have to do your job well to get promoted but this is just the basic or foundation for next level and there are a lot more.
I did have the experience that I could not promote someone that I want to promote but was forced to promote someone who I don't even think he is ready, and this was not even from my direct boss, it is from my boss's boss. If this person comes to me and ask, you think I will tell her the whole story? She didn't get promoted because the big boss likes the other guy better.
Don't get mad at your boss. Remember there are a lot of things that is out of her control and she just couldn't tell you the full story for all those reasons behind. You should not lose your trust on her unless you have the evidence that she was lying to you.