I'm late to this thread and so much has been said.
I agree in that a full frontal attack is only reinforcing her persecution complex. I made that same mistake with my wife as I am sure a lot of other people made similar mistakes. In regards to the blood doctrine, it is her choice what she does with herself. Your son, on the other hand, is a different matter.
I cannot suggest this as a course of action for you but for me, believe it or not, if my wife were in the hospital and needed blood I would try to help her in any way to receive medical treatments without violating her beliefs. I know the doctrines well enough to know that the WTS permits practically all parts of blood so in many ways they've rendered it moot plus I think that in most circumstances, there would be a reasonable alternative that would suit her beliefs. Never-the-less, there would be those occasions where a blood transfusion is required and there is no substitute (lest she die), in those situations all I have to say is she had better get her mom or someone else to have power of attorney over her as I could never commit her to death. It goes against my personal values.
My daughters, on the other hand, I would fight for.