Long Term Care is difficult. It helps if you had previous CNA or HHA experience, which it sounds like you didn't. There are two ways to play this game: 1. Talk to someone in human resources about the possibility of another preceptor. You will have to explain why you are requesting this. 2. Play her game her way, then when you're done being "trained," play the game YOUR way.
Nobody likes to admit it, but work is a game, in a way. You have to be aware of it, and you have to know how to play by the rules. A lot of preceptors do what that one is doing, because they can get away with it. However, if you know your rules, which it sounds like you do, make sure you cover your butt the whole way.
As for the ins and outs of LTC, med passes take time to get used to. You have to be effective at managing your time. The first thing I do after getting report and counting narcs is go through my MAR to make sure which residents get their meds first. I flag everyone who gets early meds. Then, I go around and talk to the residents on my assignment and know where they all are. It's important to know where your residents are located at all times. Then I check and make sure my med cart is fully stocked. I mean FULLY, including water pitcher, spoons, straws, apple sauced, pudding, all stock meds, pill crusher, etc. That way you don't need to make unnecessary trips to supply areas.
For med pass, make sure you start at a reasonable time. If you start your am or pm med pass (depending on your shift) too late, you won't be done on time. Start as early as you are allowed to (things may be different per state), and make sure you have heard everything the outgoing nurse said during report. That may give you hints as to which residents are usually sticklers for getting their meds at which times.
The best advice, though, is ASK QUESTIONS. Find someone in the facility who is positive about answering questions, and make sure you ask. If you don't ask, chances are, you will probably make a mistake. Nobody will think you're stupid for asking questions. They know you're new.
I hope this helped a little. Good luck with your job. You will make friends, you will end up fitting in, but it will take time. If you hate it, don't outright quit. Look for an office position first. Being an LPN isn't bad, but it is work...