My deepest sympathies, it is not an easy thing. I had to put my daisy down a few years ago. she was 16, and one day just totally lost the use of her back end. We tried to help her, she had pain meds but it wasn't going to get better. So we called a large animal vet and he came to the house, it was so much better than having to drive into the vet's distraught. We have a memorial garden for her, filled with every kind of daisy you can imagine!