Oh! The first part can be about suicide, you're right. The second part reminds me of antinatalism, and I think it makes sense for breaking the cycle described.
I agree with Katrisia, it's a never ending cycle. It's also an exercise in futility though, Too many uncontrollable variables.
As a son... I see it as my parents probably tried to improve what their parents did and it may not have turned out how they would have wanted the intention was good. I hope my kids will also see that even though it wasn't perfect I tried to improve what my parents had done. The last line I hope some people take seriously. Enjoy your life without kids, parenting is difficult and will bring a life of hardships... But it's worth it if you put in the effort as long as you know you can't make the perfect person. No changing your mind once you start. If you do go out for milk and never come back then the poem was true.
It's a constant fear of mine. That I'm not doing well enough. I actually lie awake at nights and that's not something I normally do. But I know that I can't do more than my best, I'll make plenty mistakes, but so did my parents and I turned out fine. As long as you give all the love and support that you can. They'll be fine. There's not much else you can do, honestly, they'll have to find their own way anyhow