LIVING WILL a.k.a. D.N.R. a.k.a. ADVANCE DIRECTIVE
talk about these things when you are healthy. know what your loved ones would want you to do on their behalf if they were to be so incapacitated by illness that they could not communicate their wishes. tell them what you would want. put your wishes in writing. find out if it needs to be witnessed and/or notarized in your state. there are many great resources for forms.tell a few people where they can find your written wishes.
we knew what mom wanted. we were lucky that we were never faced with making that decision because we didn't actually have the piece of paper to protect her wishes until a few days before she died.
have hope. preparing for the worst does not preclude you from hoping for the best. and knowing that you will be able to care for your loved one in a way that honors their wishes takes a little bit of the weight off of your shoulders in an incredibly challenging time.
do this while you are healthy so, if illness strikes, you can focus your attention on your hopes instead of your fears.