I would talk to your vet about getting those burrs out of his ears. That would be painful. About him being hard to catch...Try going out there without the halter or lead rope. Just go out and try to buddy up with him again. I don't know if your one of those people who do treats or not. But if you do, try to give him one everytime he comes up to you. Without you having anything to catch him with. If you don't do treats then when he does come up to you, make sure you prase him very well for it. And just play with him. Don't try to catch him, or try to pick all the burrs out of him. Just buddy with him a few times, and then try to catch him later on. And even when you do catch him again that first time, just brush him or something, don't try to take the burrs out yet. That way you don't lose that buddy thing again.