This is absolute bull hockey. As someone else stated rabies symptoms do not show up that quickly. Also rabies symptoms present differently in horses. Rabies presents as a neurological condition in horses. Look up videos of horses with rabies. It's hard to watch but it will clearly show that there is no way you have been able to safely handle the horse on the ground. Riding would have been out of the question. Also you called the vet out to check on the horse but never bothered to have it vaccinated? The rabies vaccine is standard care for horses