We trailer somewhere most every weekend the weather is good and I really think the horses enjoy going just as much as we do as it gets them out of the pasture. We also try to make sure the horses enjoy the trail riding as much as we do.
I guess I'm lucky as our horses just load right in....
I might offer a couple of suggestions.....make the trailer a place the horse enjoys.
So, feed them in it for a few days without moving the trailer...just get them in, feed them, and then let them get out....... and when you do decide to move it, take it slow and easy making sure they get a good soft easy ride and don't get slung all over the place.
For we wrestle not against flesh and blood, but against principalities, against powers, against the rulers of the darkness of this world, against spiritual wickedness in high places.