I'm so sorry this happened to your horse and you.
My first alert would have been her statement that she would not be riding much but the horse was for her friends to ride.
I had to fend off a pushy woman a few years ago. She wanted to buy one of our horses and it didn't matter how many reasons I gave her as to why this horse was not for her. After numerous contacts I was about to order her to never darken my door again when she eventually got the clue. And we ended up keeping the horse to her last day. I don't like pushy! Makes me wonder what they are hiding. Luckily with this woman I knew.
I am down to one horse. The neighbor has three across the fence so she sort of has friends. I would much rather have another here. At times I wonder if it's not time to find someone who would give her a good home and maybe if the right situation came along I would. But it would have to be right because once they are out of your control, well, they are out of your control.
I wish you success in finding a new owner for your guy. It's not a simple task.
If you ever find yourself in a fair fight, it's because your tactics suck. ~ Marine 1SGT J. Reifinger