I have this really bad, and not just exclusively for family. Death anxiety is one of the scariest things, in my opinion, because death is so final. I have religious-based OCD (where I feel the compulsion to constantly pray/has Christian themes as the backdrop of most of my tics) and its always preventative stuff - doing this will prevent my grandparents from dying, or doing that will save someone's soul. But, I've realized that these thoughts are irrational, and there's nothing I can do but make the most of time in the now. I try to become a little more mindful and live in the moment as time goes on, rather than plan and think about things in the future I have no control over. But yes, I and many others definitely do battle with the same thoughts.