Right. Sometimes, the saddle seems perfectly fine to us (and a fitter), but if the horse clearly says no, we have to listen to the horse. It probably will require trying different saddles, and unless when you get a good one the issue totally disappears never to return, then you are still facing some risk of injury as you experiment with new saddles.
While it sounds like where you mount is also part of the problem, I’d hesitate to stuff her in a more enclosed area to solve the problem. Since she did it once before, I don’t think it’s just the rehab crazies necessarily.
Friend of mine is a trainer who had a horse in training that was high anxiety about standing. On the cross ties. At the block. Anywhere. But also a sweet horse who did not try to be naughty. She’d kind of stuff him into a corner to mount and just get on with it. Until the day he reared and sat/slid down the kickboards because he didn’t have anywhere to go forward and was just as anxious as usual. This incident definitely didn’t help the problem.
I taught him to do the parallel park thing in one session, and he seemed to really get into doing something to use his brain in hand. By the time my friend got on that day, he stood like a rock until she asked him to move. YMMV but I’ve rehabbed several horses including my own in the past few years, and once I got good at teaching it (using my horse for practice), I now teach it to all of them. I think with rehabbing, you often run into saddle issues as they change/get back in shape, you might have tummy issues/ulcers, excess energy causing hyper-alertness, they can be cold backed, etc. The method seems to help them all. For some it’s a huge improvement. For others, you might need to combine it with some other R+ type reinforcement or go through some other groundwork to test their anxiety level first.
