My wife and I don't have children but are very close to our nieces, nephews, other family members and friends. I can't remember a day when there wasn't at least one person who drops by for some reason or no reason at all. Fortunately, I'm too busy to mope around in my old age. Thanks anyway,
There are a lot of people with children and grandchildren who never visit them as well. Life is kind of messy like that,
Family is ups and downs, just like friends and maybe worse. But for me I'm glad I have that extension of a child and grands...' In my retirement I'm not busy but had a very busy working life and raising child and grands and boy friends... and lots of fun with the work.
Again, being "selfish" is not a flaw nor a sin nor "bad"....it is simply doing what YOU want to do. If your parents want you to be a doctor and you become a garbage hauler are you being selfish? Do you HAVE to do what they expected? Are you a criminal for being what you want to be, doing what you want to do? Are you a bad person? Sheesh, Get "selfish" in perspective......
There are degrees of selfishness. The self preservation impulse is instinctive and healthy. And I can see the case for not wanting to further populate the Earth. I was certain I didn't want kids before I got an advanced degree, with the capacity to earn a living, and then got married.
I think some people who had kids and regretted it want to make those who didn't have kids ( and so have it easier ) feel guilty ....but it isn't working