I've seen this "kids are insurance against loneliness" logic repeated often, but I don't believe this bares out in reality. I personally know plenty of child-free older couples who remain quite happy and social. I also know plenty of parents whose kids don't speak to them anymore or whose children have lives on the other side of the country/world. Anecdotally the loneliest older people I know are ones who have put it upon their children to keep themselves from loneliness.
> And despite all that, we love them and we want to have them
As a parent I always find it funny that we need to add this to every statement of frustration of family life (I'm not critiquing you, I also say this every time I mention any frustration about parenting). It is worth recognizing that saying the contrary is fundamentally taboo. I find this to be another under-discussed challenging of parenting: you can never even entertain the idea that "maybe this wasn't what I wanted"