You are using modern day liberal standards
Not at all. Even Jesus, who you cannot accuse of modern liberalism, looked at things that way. When there is no accuser then there is no condemned. So don't accuse people. "Forgive us our trespasses as we forgive those who trespass against us."
People in the ancient world were different many ways, but we have also a lot in common with them. For example, parents loved their children, husbands their wives, and people tried to live happy lives.
Above all, people could think as well we can today, but obviously they had not as much information and technology. In particular, the processes involved making decisions are much the same as those we use today.
If in the ancient world a wife had an affair a man would think though very similar questions as he would today. First, who actually knows? He would not appear to be seen as an "inadequate" husband. So even if he finds it hard to forgive his wife, he will try to patch things up if that is possible. If not, he may seek a divorce. Again he probably would not advertise the adultery as it makes him look bad.
There may be rare cases when the whole thing is public knowledge anyway, so anger and fury may then drag him and her to the court and accuse her. Then the ancient rules of evidence would kick in. Unless there is a confession by both parties, or some eye witnesses, which are rarely there in adultery, the case would fail.
However, both the wife and husband as well as the "boyfriend" would be asked to move to a different community and start a new life.
Similarly, if you have a son cursing his father, then the first thing the father would think of is the scandal, followed by a consideration for his son: this would be in the ancient world first and foremost, if my son is dead who will feed me when I am old?
He will therefore attempt a reconciliation, and if that fails, he will send away his son, in the hope that at least further harm and scandal has been averted.
Court cases in the ancient world were much rarer than they are today, and litigation was avoided if at all possible.
BTW.... you do not catch gangrene from adultery.
Also, the story of the adulteress in the gospel, is not a proper court case, it is more a like a lynch mob. As I keep telling you, since the Roman conquest of Jerusalem (63 BC) the law of the land was Roman Law, not Jewish law.