There are lots of people who regret having children. Many credible studies have been done on this topic -- not ones from religious organizations, that is -- and regret or mourning a lifestyle one never got to live is quite common. Not a majority, but it's common. Just as regret is common over not having children. And all this really says to me is that it is in the nature of humanity to wonder about the road not taken, whether that's children or no children. There are also some people who are just plain unhappy, and would be regardless of their path in life. They're just wired that way.
I give the writer a teeny bit of a pass, since she states right in the first sentence that she just had a miscarriage and wants but has been unsuccessful in having children, it's obvious that she is not in a position to give a rational opinion on the topic at the moment. But that's all the more reason not to write reactionary pieces like this when you're dealing with something that throws all hope of balance or neutrality out the window. I guess this is why I don't like opinion pieces though.
I would not want to live without children now that I've had them, and have for most of my adult life. I don't believe that just because I would feel a certain way, others must too. I would also feel empty without my horses. I think they're just about the best thing ever, other than my kids. They're almost equal to my kids in my mind (not in a 'child and horse both dangling off the cliff who do you save' scenario, but just about everything up to that!). I've ridden since I was 3 years old, have never been without one since and that bond with the animal is crucial to my happiness in life. Does that mean people who are afraid of, don't like, can't afford, or just don't care about horses are living an empty shell of a life? No.
If there's anything that irritates me about people, it's the insistence that their values, their joys, their beliefs, their passions, are the one true way or a superior way, and those who choose something different can't possibly be happy, fulfilled or balanced without it. It disturbs me that large family parents (not specifically you guys -- generally speaking from RL and other experiences over time!) are often especially condescending to the choices of childfree people. Aren't we in the same boat as they are? Don't people with no kids or one or two kids often degrade, question, scoff at our choices? Don't they assume that we could not possibly have a quality of life equal to that of "normal" families? There's a thread here filled with tales of others people's nasty, uninformed, and condescending opinions, comments, attitudes that we've faced for our choices, including the accusation of selfishness turned around on us for having so many children. Should we really be discussing the choices of others in the same way?