Join Date: Jun 2009
Location: British Columbia
Taking a different horse isn't going to help fix your current horse, is it?
You should bring him to the show, tie him to the trailer or put him in a stall and let him get over it. Have you taken him off property much? It doesn't sound like it- and you can't expect your horse to be an angel the first time you take him away from his buddies.
Try to get him off property as much as possible, with other horses and on his own, even if you're not riding. It's a bummer to not be able to show when you want to, but once he's learned that throwing a hissy fit isn't going to get him what he wants / not being able to see his buddies isn't the end of the world it will be a much better showing experience for both of you.