But realistically? Bones are the density that they are for a reason. You have stronger and weaker bones in your body, but that doesn't happen haphazardly, so if you go about changing the composition of her bones, you're going to have other problems. If you make the bones in her wings more dense, then she can't fly. If you make bones in the skull too dense, then you'll have pressure on nerves and lose sight or hearing, for example. Make the bones too dense else where and you'll have pulled or strained muscles trying to compensate.
Also, having a passive magic that caused wounds to instantly heal could also help with her healing. If she was like Wolverine in that respect :P