Hondo, Scully is right, the blood issue has become a big mess. First of all, I'm sorry that your wife is now an ex. That leads me wonder why you are concerned with this at all. What she may or may not have done with her blood card would probably not have had any legal bearing on the situation had she needed blood and you were still her husband. A couple of fruit loops running up and telling the doc, "Oh she was in my congo and she told me that she would never take blood!" wouldn't hold much water with her husband standing there saying, "Okay, do it."
But, don't let the medical types fool you into thinking that there is nothing wrong with it and it's perfectly safe and blah, blah, blah. That is simply not the case. You have to remember that blood tranfusions became vogue and the instant cure-all to medicine back when mercury was used to treat syphillis, i.e. one rung above witch doctors. And like penecillin and an "organ uplift", a "blood exchange" was once considered "good for what ailed you". Taking blood, it's derivatives, it's substitutes, it's fractions, etc. is medically, a very serious thing, in spite of what the medical professions propaganda ministry would like everyone to believe. There are a near infinite number of problems that can arise before, during, and after the administering of blood.
That said, it doesn't mean that there won't be a time such that if you don't get some more of your blood into your circulatory system you with die until you are dead. That can and does happen, and it doesn't matter where or what the circumstances, you will be in the midst of a very emotional scene. The issue for JWs comes down to the beief that Jehovah is going to be pissed if you (or your loved one) takes blood. IBut, if Jehovah gets pissed, that kind of flys in the face of the "life is sacred" concept, doesn't it? If a person refuses blood, knowing that they will die as a result of their decision, are they not committing suicide, which is supposedly as verboten to Jehovah as taking blood, isn't it? Now for the most extreme case (and therefore, the one everybody always cites) your child is dying without blood, now what? JWs say that if you allow blood, there is no absolute garuntee that the child will live, but I've never seen that as proving much. There are no absolute garuntees at all, are there? My slant has always been kind of a loophole thing: if I okay the administering of blood to my child in an effort to save his/her life, the responsibility does not lie with my child but with me. Therefore, if the child dies, Jehovah will not hold the blood issue against the child. But I can be held accountable, except that I have been willing to sacrifice my well being (everlasting life?) for the sake of another human being, and that, we are told, is the greatest example of love a person can show. And since love trumps all of the virtues, at the very worst, the love example should offset the decision to allow blood, and we will simply have to replay the down.
What I have seen as far as the blood issue and the blood card and the medical notifications and so on was that they were, to most JWs, a kind of antagonistic badge of honor/acceptance. Kind of like those tattoos that various special forces troops (French Foreign Legion, SEALS) wear. Y'know, the ones that say "Jump or Die", or "Death Before Dishonor". Hey, I got a blood card, I'm now a made man!
I hope I haven't confused you more. But when you get into the aspect of choosing reasons why death would be preferable to life, you're into heavy duty opinion.