Not all healing is etheric in nature. Spiritual healing in the strict sense of the word takes place much higher on the planes than that. The MOE model of healing has it that all illness has its roots well above the etheric level, on the spiritual planes, and if the spiritual basis can be changed, the illness goes away naturally. Since spirit is nonlocal -- space and time do not exist for it -- nothing prevents you from sending spiritual healing to the far side of the world just as effectively as sending it to the other side of the sofa.