As everyone else has said, I would no be riding this horse yet. Even though you see times when she doesn't seem to be limping, those may be due to a change in the surface of the ground --not so hard or rocky. The fact that it took so long to get the infection cleared up and the hole isn't healed yet means that it's very possible that there is some serious damage inside the hoof wall that you can't see. An inflammatory response like your horse had for so long will damage the lamina of the foot. You also don't know what kind of damage was done to the tendons or the bones in the foot since there were no x-rays done so you have to really take into account that your horse is likely healing much more than just that little hole that you can see.
Time off until she is able to walk and trot pain-free on hard surfaces would be your best bet.
Licensed Veterinary Technician