The way that I see it whatever happens in this world after we are gone could never be our concern as we simply won't be there at that point, and anyway we all have to cease existing someday and eventually most of us very likely won't even exist in the memories of those who continue to stay here.
Grief and loss are just an inevitable consequence of people deciding to procreate, I wish that nobody would procreate in the first place so that nobody would have to die. And even if choosing not to delay the inevitable makes other people feel sad, none of us are obligated to continue existing here, it's a personal decision deciding when to leave.