I woke up reading about this post. This man's woman cheated and had a baby that was not his.

To a man, rising a kid that is not his is akin to r*ape and slavery, the worse of both, because he could use those resources to rise his own kids instead of a product of his wife's infidelity. He is basically a slave to a woman and a child that did evil to him. It is basically the evil of evil: rewarding bad people and making good people pay. In the past this happened, but also punishment for adultery was harsh so the possibility was lower that he was cheated on to rise a kid that was not his, but fidelity and morality is being eroded. Even TV makes cheating looks like it is not a big thing. It is even scarier how many women think that it shall not matter who the father is... well, it does, because all the implied sacrifices of parenting and the fact you are rising the kid of people who basically humiliated you.

Of course, our society assumes good faith and punishment is not used anymore, and what is good or bad is not clear anymore because of moral relativism. I doubt we will ever return to that, but we can turn to watch for consequences.

We shall focus on consequentialism and thanks to tech we could easily, for example, know if a baby is of his father by just a simple DNA test. Trust is not required anymore, and the fear of the shame may at least defer her from cheating, and make the father at least rest in the fact his kid is his.

But this is only one aspect. Men already suffer social and legal consequences for cheating and leaving wives, family courts are very harsh to them, losing even half his stuff, but it becomes very unfair when courts even make them pay for kids that are not theirs. The point here is to balance consequences between genders and that will help the relationship between them. There may be no true fidelity, but at least consequences can make for it.