Aging and death

I’m not sure if this is the right place to post so please excuse if it’s not.

I have an uncle who is in his early 70’s. He isn’t ill with any major terminal illness. He is pretty much closer to me than my own biological father (who I did not grow up with). My uncle however I’ve known since I was 0 months old. While I know (statistically) he has many years ahead. I have to admit that I already have this fear and dread of losing him. So much lately that it’s just crippling. I just wanted to share. I know it’s not the same compared to those that are experiencing expectant loss. I just wanted to put down my thoughts. Thanks for reading.