Also, make sure she is getting a gentle ride. My husband’s
horse came to us with quite an attitude about getting into the trailer, used to
even pull hard and suddenly enough to get the rope away and then run off down
the road. Of course, then he’d come back when he realized none of the
other horses were going to join him. He eventually gave it up, after some body
work, and very careful driving. I’m convinced his previous owner (or
maybe even the one before him) took the turns just a bit too fast, braked a bit
too hard, took off with a little too much power, etc. The previous owner said
no sense trying to fix his loading problem, he’d been like that for 4
years and nothing anyone did ever made it any better. The horse had been trailered
a lot, the owner was a runner so would run with the horse, then get on him and
ride back, so he wasn’t avoiding the hard work, there was none. It took
the horse about a year of gentle driving (and one or two sessions of body
work) to load consistently, without anxiety or refusal.