Obviously, we can't help who we fall in love with, and for most women, the probabilities wouldn't prevent them marrying. Most will know that their older spouse will likely die a long time before them), but what they don't visualise is how long the illnesses can go on for.

Yes, some of them might have a quick or sudden death, but most ageing people have years of 'issues', like Willis. It's not only draining on the younger spouse, but has a tremendous impact on children who grow up with the illness, dreading the day they're going to be told their father (usually) has gone.