I think you do fear death, given that you plan to live until it is physically impossible for you to do so painlessly. If you don't fear death, an easy and reliable way to avoid suffering in your old age is to painlessly commit suicide right now. But be aware that we treat people who don't express a preference for staying alive as having a serious mental illness worth locking them up for.

Fear of death is not just natural, it is the most fundamental instinct of any creature besides reproduction. Those who don't have it, don't last long. Perhaps society's attitudes towards it could profitably be improved, but don't make out like it's an irrational personality flaw.