This might help. Try telling her the whole bit from Genesis about men having to work from the sweat of their brows. God doesn't want to just give or protect you from everything when you have the ability to help yourself. The same way that a parent teaches a child how to protect itself, instead of always being there to protect it themselves, so that it can become self sufficient. That means doing what you need to do so that you can be healthy. If not for her own self then do it for the people that love And care for her.

And if that doesn't do it hit her with these verses.

1 Corinthians 3:16-17

   16 Do you not know that you are God's temple and that God's Spirit dwells 
      in you?

   17 If anyone destroys God's temple, God will destroy him. For God's temple 
      is holy, and you are that temple.

By not getting health insurance she is not fully trying to take care of her temple, and in this scenario she could be seen as the destroyer. If her body is a housing of God then shouldn't she get some sort of insurance to protect it from the possibility of damages?