barn and buddy sourness

Question
I have a 3 year old standard bred gelding.I just bought him recently from a mininite. He said that he had just started him on neck reining but he was well behaved so we bought him.He has become very attached to another of my horses and every time a friend and I go on a ride together he hates to be away from her and tries to bolt towards her.If she's not around then he tries to bolt for the barn or the  tack room where we put his tack on.He tosses his head so its a little hard to turn him.When she is away from him and he can't see the barn he is a good attentive horse. We have him in a broken snaffle bit which is the bit that the mininite used on him.Can you help me with the barn and buddy sourness and give me some tips for stopping him from running off?I usually manage to turn him but my cousin won't do it so is there a better way? I enter in horse shows and my cousin and him are going to be in them soon too,whenever they are ready.So this really needs to be fixed. Thanks!
-Madison

Answer
Trust me when I say this is not an easy fix; infact, I'm still in the middle of fixing this with my horse, Victory. You are going to have to separate them put them in stalls at night and have them in different pastures during the day if you can. Anyway you can separate those two completely would be just fine. He is just Herd bound, and this is just a natural thing for them to want to stick with their herd. If they can stand next to each other on each side of the fence it might make the situation worse so try to make some distance between those two.

Victory also has a habit of wandering off towards the barn too, so make a habit of getting off of your horse in another spot and loosening his saddle there, make him feel comfortable away from the barn as well to show him that the barn is not going to save his butt. If you can take him to horse shows with you and have him stand at the trailer by himself the whole day do that, don't park a horse next to him and he will learn to be away from the "herd". Also if you have a round pen make your cousin start working him in the round pen and practicing more in an arena, if she cant control him herself she shouldn't be riding him, so just teach her to be a bit more aggressive when she wants him to stop or turn his head, she really just needs a bit more riding time with him alone with no other horse around.

A tie down will also help with his head throwing habit, and I'm sure he starts to stiff neck a lot of people so a little more tug may work. Perhaps the snaffle isn't working now so you may need to switch to either a harsher bit or maybe even a hackamore.

the first and second paragraph will help you with both his running off and buddy and barn sourness but here's another tip. If he tries to run off simply turn his head to one side and start spinning him around in circles, a horse can't move straight if its head is turned; if you are constantly pulling on his face to just stop him he's going to get use to it and start pushing against it, making it harder and harder to stop him every time.

I hope this helped you a lot, and I hope that you and cousin have awesome times in future horse shows! Good Luck!