Now that my *rant* is done, your final question is, "are you going against your boundaries?"
The real answer is to your question is the answer to this question: "What are your boundaries?"
Is this private land, family land, your family, her family, shared family?
Unless it is your private land owned by your immediate family, you have no rights.
I will make an assumption based on the statements you made that this is shared family property. Maybe your great-grandmother's? You are both keeping your horses at G.Gmothers? Then you really don't have any rights.
All you can do is take the matter to the adults (or property owners) and ask them to set boundaries and rules.
Or, move your horse to a place you have more decision making ability. If you were at a barn, paying a monthly board fee, and the owner's dog behaved this way, what would you do?
Hit THEIR dog? What if they said, NEVER touch my dog? Well, the response on this forum would be, MOVE your horse.
Sorry, didn't mean to lecture (again.) But those are the options as I see them.
Last edited by AQHSam; 02-10-2012 at 01:16 PM.