Nonsense!!! I respect that you reasoned to a conclusion, but your argument is flawed and cherry picking parts of what I said.
I can only hope you’ll spend some time thinking about the relationship between law and sin.
You yourself say the sin is grave. I cited Incest laws to show a clear example of the Church’s authority in dissolving marriages. You’re also ignoring that the Catholic church (even today) teaches little kids that without sin entering the world, there would have been no birth defects, no child bearing pain, no disease; No incest. Who knows, the OP might have married a close cousin. He also asked me to elucidate on sin, so I think I’m on topic.
Consider a legal case about marriage and validity (who knows the wife of the OP could be a half sister): Abraham married his biological half sister. But if Adam hadn’t sinned, there would be no incest law at any time in history. So why does it matter if Abraham commits incest or not? Legally speaking, our salvation depends on the messiah’s lineage; and God refused to acknowledge Hagar’s rights because the promise God was to Abram before Hagar but after Abraham had intercourse with Sara his half sister. I’m not spouting a theory, but paraphrasing the very words of the old testament. If incest law was ALWAYS in effect as absolute divine law, then God would not have acknowledged Sara as Abram’s wife.
Sin and the effects of sin are the reason for legal definitions of validity, tracing of lineages, marital rights, etc.
Roman’s 5:12. Therefore, just as through one person sin entered the world, and through sin, death, and thus death came to all, inasmuch as all sinned*— for up to the time of the law, sin was in the world, though sin is not accounted when there is no law.
I am a citizen of two kingdoms, a natural one called the United States of America; and the supernatural body of Christ.
If I were ignorant of church law, and married outside the Catholic church I am equivalent to a man on a temporary journey in a foreign kingdom. I decide to “do in Rome as the Roman’s do” Under that law I contract a marriage and live in a country under their VALID jurisdiction. I am no different than a Gentile (and I really am no different!)
Romans 2:14 “For when the Gentiles who do not have the law by nature observe the prescriptions of the law, they are a law for themselves even though they do not have the law. They show that the demands of the law are written in their hearts, while their conscience also bears witness and their conflicting thoughts accuse or even defend them on the day when, according to my gospel, God will judge people’s hidden works through Christ Jesus.l”
This has happened many times in history; Judges 21:25 “In those days, there was no king resident in Israel and everyone did what was right in their own sight.”