Please help..!? advice needed?

That is horrible!!!My trainer used to use my horse for other kids(a few years ago-but I am in middle school) but as soon as I asked her to stop, she did. I think that you should sit down with your trainer and talk to her. She has no right to use your horse. Also, if a girl falls off, and you have not signed papers, they could sue you. I do not believe that this is good for you OR your horse in the long run. I would tell them that you WILL change barns if that's what it takes. I would also tell them that you are able to bring authority(which I wouldn't, but I think you could) into the situation. She has absolutely no right, and it could be damaging your horse. I would also find out who the girls are riding your horse. I would call their parents and let them know that the horse they are riding id not under insurance. They may feel differently if they know that the horse is being used illegally. I would also tell your instructor that you had alot of trust in her, but not anymore. Also, this is hurting all you have worked for. You and your horse have worked to gain trust and become better. She has no right to tear that down. If you have to, I would change barns. I am so appalled by her, too!!!!she haas absolutely NO right to do that!I am so sorry!