Help Kura have a happy, healthier life

Hi I'm Sam. My dream horse Kura (Please note: She is not my horse and that's why I need your help), has been neglected by her owner (as she is scared of Kura). So I was looking after her and she seemed happy and was looking better (Note: The photo is after I brushed her and we fed her). Then the owner decided to move her to a "better" place with company of other horses etc. Recently I went horseriding and we saw her a few blocks down from where she had been kept when I was looking after her. We patted her and said 'Hello' but she was jumpy and kept nipping us. She didn't look happy, instead she looked scared and her coat wasn't brushed. There were no horses like the owner had promised either. We have made an offer to buy Kura but the owner has knocked back the offer. We can't understand her logic, she is scared of her horse and she doesn't do anything with it let alone look after it.
The point of this petition is to try and let the owner see how devoted and how much I care about Kura, so that maybe, just maybe, she will let us buy her.