This sounds familiar, perhaps you and I have discussed it before.
My life matters to me as a vehicle for what truly matters: if my descendants are thriving, and my values are upheld, whether I am physically here once I've contributed to it, is completely irrelevant to me.
I will fight to live as long and as well as I can, but only because that increases my opportunity to contribute what I want. Merely "existing" is not my highest value and therefore is not the thing I worry about solely.
It's certainly possible, but I've seen others here express the same sentiment. Another poster once posted a quite insightful comment about Nietzsche that really described a lot of the problems of nihilism that captured the feelings that I've had since realizing the unreality of religion at a young age, so I'm not exactly alone even if I am a bit of an outlier.
It goes back further than that. "To be or not to be" is indeed THE question, or rather THE choice, especially if you have the type of personality that tends to lead to an existential crisis at some point in your life.
In the end, as far as I can tell, there is no obvious "meaning" in life beyond what we decide to attach meaning to. And "to be" is a prerequisite for most objectives we may attach it to.
Having offspring can be seen as an extension to this. It is to decide that "beeing" will go on even after you as an individual dies.
My life matters to me as a vehicle for what truly matters: if my descendants are thriving, and my values are upheld, whether I am physically here once I've contributed to it, is completely irrelevant to me.
I will fight to live as long and as well as I can, but only because that increases my opportunity to contribute what I want. Merely "existing" is not my highest value and therefore is not the thing I worry about solely.
Hard to explain if you don't get it.