Recently, I've been experiencing burnout that interferes with my ability to do this. It will pass, with time. But it's easier to think about that the longer my life will be, because I would have lost a smaller proportion of my limited time to it. Repeat for any other thing that one might view as wasted time, and it adds up.
The question you've turned this into in your last paragraph is a completely different one. I don't have any desire to outlive or not outlive any particular person. It's nice to have the company of people I like, but my sense of meaning, to the extent I have one, is unrelated to that. People move into and out of my life all the time for various reasons.