Ex Racehorse Thoroughbred Mare?

i retrain a few of our race horses before i sell them as hacks. Usually i start out with ground manners. Some of them lack this. Try taking her out and leading her around. A big thing with themis that they are used to routine. So i just take them in hand for a few sessions to graze and walk calmly with me ect. Then do some trail rides where you go nothing faster than a trot. A lot a people think ex racers are crazy (ok some are) but mostly i would classify them as reactive. They have been taught their whole lives to react very quickly. You say she rushes. Thats normal. To her its not rushing but to you it is. You have to try exercises that teach her that she is not going to "work" you are not going to ask her to gallop ect... Ride on longer reigns and keep your hands down then slowly adjust to ur style of riding. The circles thing doesnt always work immediately as she may find it confusing and get a bit nervous. Try to approach her training from her mental viewpoint. Schooling is a whole new thing for her. You will have to introduce leg aids slowly as she might over react to that as well. The quickest way i calm down our horses is by taking them out of stables and keeping them in a pasture for the whole day and sometimes night. I will leave them in a paddock to rest for about a week and then start schooling. Start your schooling in a fairly large arena as her scope of movement will probably be quite extended at a canter so small arenas wont give enough space. But as soon as she gets used to the aids that you use and what they mean she should adapt to ur routines pretty easily