Jamie, get a counsellor involved in this- if you do not trust the school ones, do you have a Pastor??
You can also get independent help- over here we have a thing called "Child Line" where you can ring up and get some answers or just tell your side and get listened to- I will see if there is a version in the States.
I am sorry folks but, coming form a home where I suffered mental abuse most of my childhood, (NOT form my Mother but, much as I loved her she screwed me up , too) ...Parents are NOT always right, and parents do not always know best, and parents are often so wrong they are the WHOLE problem, in which case they do need help to prevent them messing the kids up.
What you appear to need here is an independent , experienced person who can tell yo which of the options is correct.
At your age, if your Mother is not willing to listen to the mediator(if they think she is at fault) the decision may be far harder than merely getting rid of the horses.
I think to do this is a putting a band aid over a gunshot wound, and I think, if things are exactly as you say, she will soon find some other thing that annoys her.
Been there, done all that!!
Get help.
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