What do you do with all that Health?!

What do we do when the truth would be just too scary? I mean, to tell to another person.
I have posted before about my mother's hypochondria. Just take my word for it--i've known her since before I was born.
There always seems to be something wrong with her. She is hardly recovering from one thing before another another strikes. It has been the cause of much disappointment for my father, myself, my sister.
I can look back at my childhood and pull up many images of myself sitting on my packed suitcase, hearing my mother's soft crying, my father's soft voice, and then suddenly my mother's loud crying "why doesn't anyone feel sorry for me? can't you see im sick!" and then, shortly after, my father appearing in my doorway to inform me that we were no longer going to palm desert for a week, or to Europe for the month.
I remember my father driving me home from school on Fridays, date night for my parents, and him calling my mother on speaker phone, reading her the movie times and restaurant reviews but only getting halfway before my mother cut in, "not tonight. im not feeling so good."

The truth of the matter is that, moments in which other people can and have pushed themselves through it, my mother has not.
After enough date nights, enough trips to Europe or Hawaii were cancelled, my father's infidelity kicked in. And I will say this now, my mother's hypochondria was not, it was NOT, an excuse for my father to do this. There is no excuse, of course.

However, my mother has a new husband now. And when she cancelled on him yesterday he said "i think this is all in your head. i think you could get up and come out." Part of me wanted to shake his hand. When my sister and I heard this, we turned to each other with our eyes nearly popping out of their sockets.
"Someone finally said it?" we whispered to each other.
Yes, i wanted to shake his hand. But also, partly, I wanted to shake his shoulders and say "you dont say that to her! Dont you see? She can't handle that!"

What will she think then? That my father's infidelity was her own fault? That she must, in fact CAN, do more, MORE?? I mean more with her life, with her time. The truth is, her health and her house are her life. She is her own biggest problem, it is true. Her physical health is what she has always devoted all her energy and time to. When her friend had a concusion last summer, she continued to go to work, to go to dinners with her friends, to visit her daughter at school. When my mother had a concusion, she cancelled her trip to hawaii. That was scheduled for two months after this concusion. She saw a doctor every week for 6 weeks. She cancelled all of her lunch dates. Her health has always taken precedence. But the word i'm looking for his hypochondria. That is what has always taken precedence.
I don't think she would know what to do without that. She is 53 years old, and no one has ever said such a thing like that to her before "I think it's all in your head."
Is it too late? Is it too scary?