I am dealing with these fears too due to my illness @chordy. I just try to treat the symptoms, keep doctor appointments and I research NDE’s online as well as look into spiritual , inspirational things from time to time. At first when I got diagnosed with COPD and put on oxygen I had so much death anxiety but with time and reading about it I’m coming more to terms with it. When you think about it our age and health by itself isn’t always a predictor, some people live long live’s with age and even some illnesses but at any rate looking into it a bit has helped me settle some although if my symptoms are bad sometimes it scares me. I try to live as fully as I can and distract myself with interesting things. I have no control of when I pass but in spite of physical and mental illness I can enjoy what time I have left, however much that is.