Some thoughts on your processes... Hope they help you better understand & analyse what exactly you're doing & why.
lead over withers, me pointing like an idiot... her looking at me with that confused look.... then 'tap.. tap.. tap..' w/ the stick behind her elbow. Bigger confused eyes..... then I reached up and took the lead hook and pushed away from me while tapping. She took a step - Stopped tapping and told her how brilliant she was
Anyway, after about 3 minutes of that, she got what I was asking. So she knows the behavior... just probably had been asked a different way.
Do keep in mind, horses don't 'know' something in a general sort of way like we can. They learn to associate a 'stimulus'(a cue in this case) to a behaviour, with instant consequences of it's action. So...
That the horse didn't immediately just go where you pointed, especially after you started tapping her on the girth line(behind the elbow?), she DIDN'T know what you wanted. But when you *directed* her with pressure on the halter, then *reinforced*(quit tapping her) the Right behaviour, she 'got' what you wanted, and with some repetition, started to learn it. So YOU taught her that, worked it out by yourself! Bravo!
To be particular, if you want her to walk forward, I would put forward pressure on the lead(direct) while putting some pressure out *behind* her, or tapping her tail. If you want her to turn her forehand away from you, you can push her face away from you(direct) as it sounds you did, and put the pressure at or in front of her girthline.
2) Next, led her to the trailer. She started getting worried. I tied her to the ring on the trailer, and spent a good half hour grooming until she got very relaxed.
Remember, 'short & sweet' is far preferable to long sessions. If she was nervous just approaching the trailer, I would have approached... and then retreated, numerous times. As well as rewarding her with Good Stuff(perhaps grooming is particularly pleasant for her, perhaps there's something else...).
5) walked her back around tried to line her up. head up and very busy feet. so we just went slow. She walked in first time, but wasn't happy about it and immediately backed out.
Baby steps is best. If you've acknowledged she's nervous even just approaching the float, I wouldn't rush to getting her to go straight in(regardless that her previous training has taught her to go in regardless of her fear), but would take her to whatever spot *she* could *comfortably* go, then 'retreat' again *before* she felt the need to do it herself. Remember, associations are EVERYTHING to a horse, so you DON'T want her to 'practice' more feeling worried when entering, or backing out of her own accord when she feels the need.
Praise, and treats (don't judge me... I rarely give treats, but she's very food motivated and was being quite good).
Horses learn from *instant* association. Consequences need to be meaningful to them. So 'praise' for eg is innately meaningless *unless* it is associated with either a reward or cessation of something Bad(negative reinforcement. Whereas food is a 'primary reinforcer' - that is, it's innately a Good Thing, that can be used of itself, or paired with something like praise to associate those noises with Good Stuff. Just remember, careful to never inadvertently reinforce/reward Wrong behaviours with whatever you use.
6) Friend declares it time to load both horses and go for a drive.
Your friend is going way too fast for this horse IME. You know you CAN get her to load. But I thought the aim of the session was to get her to load *confidently*.
latched the doors QUICKLY, hooked her up through the window (a little challenging - but we got it done).
I disagree with whoever said don't tie them until tailgate is closed... or whatever. You FIRST need to ensure she is CONFIDENT being tied in there of course, but I'd absolutely tie(well, to start with, control her head with a very long rope, wouldn't hard tie her) before shutting her in. What if she panicked & reared & spun, got stuck over the divider or such?? If you have to latch the door 'QUICKLY', that is a sure sign you're doing too much for safety. Tying her through the window sounds just risky & awkward, with a fair chance of failure. Set yourself up for success every step of the way.
I did defer to my friend's judgement on that. She felt it was time; that we aren't training - just refreshing a memory
You ARE INDEED training!! Whether or not she's done it many times before & was fine, EVERYTHING you do with her is either 'training' her to be better at it, or to be worse. And it sound like she WASN'T at all fine, so your task should have been to TRAIN her to become more comfortable, confident with it. The way it was done, she could well be worse next time.
Had there been huge drama, we would have dialed it back and set the expectations lower.
Don't wait until 'dramas' happen, huge or otherwise! Strive to work in such a way as to avoid, or at least minimise their likelihood greatly!