Hello Aurora (goddes of the dawn and of new beginnings!!!!!)
Don't let this supervisor push you out of a job that you like (if you like it) and that pays well. She CAN'T be top of the heap unless she owns the company. There's ALWAYS someone higher. But get your ducks in a row before you go over her head or she'll make your life a living hell.
Go right to her and SAY TO HER: It seems like I'm not doing the job to your satisfaction. Am I on target in my training or behind? Are there specific areas you'd like me to focus on? I'd like to do well in this position because I like working here but it frequently seems like I'm not meeting your expectations.
Did you see the trick there? Not ONCE did you accuse her of being nasty and mean. You're ASKING for direct and specific feedback. Mark down the date that you have the conversation with her and the outcome. If she continues to berate you THEN you have "ammunition" to bring to her superiors. I might also suggest that you do a little follow-up note to her (if you choose to ask her about your progress) that recaps your conversation so that it's IN WRITING and in your personnel file. Of course, keep a copy yourself!
If you think it'll come to her firing you - document document document EVERYTHING so that if your unemployment is challenged (and it can be), you have a paper trail or notes to support your case. Trust me, companies do NOT like having to pay unemployment and will do their best to avoid it (and to hell with you in the meantime). You have to watch out for YOU.
Now - holiday blues. Listen, sometimes family makes the holidays even worse - like HELL actually! I'm not suggesting that you have it "better" without family, merely that a family may not make it happier. You make a difference in someones life by volunteering; what could be more "goodwill toward men" than that? YOU are doing what the season is all about.
So you cry...no big deal...I cry at certain christmas songs - - - just because. I don't think that makes you nutty, just emotional.