Your post was an odd understanding of what "rational" means. Just by the way you are using the word in your post. We can't use rationality in the realm of someones psychology (why he did this or why he chose that), much more God's. The mind of a man who abuses a woman isn't a rational mind for example.
We are talking about rationalism in the context of wisdom -- when dealing with circumstances and situations in real life.
Do you think the words of Paul also counts towards Carole Ann Boone (who was married to Ted Bundy?); Do you think Jesus would tell Toni Henthorn to remain faithful to her husband --who not only abused her but eventually shoved her off a cliff? Or what about that Colorado Dad who killed his entire family?
You christians don't think of stuff like this yet for some reason demand a verse in the bible to answer something that should be so obvious. There are circumstances and situations that the Bible doesn't reference or answer, one verse in Ec 3 about a time for everything (which includes killing) because everything has their own circumstances and situations.
What should happen in that case is a Matthew 18 trial by the congregation, and in situations that would result in such extreme tragedies, the likely endpoint of a Matthew 18 trial by the congregation would be the expulsion of the husband from the Body of Christ.
Then the question would be whether the woman would prevented from remarriage or permitted to remarry--which is the additional point that Paul had to actually find a way to make practicable. In 1 Corinthians 7, Paul talks about Christians married to Christians and then gives
different instructions to Christians married to pagans. After the Matthew 18 trial, the woman's position would be "Christian married to pagan."
Some people seem to think that Paul's instructions to Christians married to pagans are the same as they are to Christians married to Christians. They say that Christians married to pagans are also only permitted to separate and must eventually reconcile.
If so, why did he address them separately, and why did he not say the same thing? The fact is that for Christians married to Christians, the Body of Christ exercises control over both of them. Both of them are expected (at least in Paul's congregations) to continue toward reconciliation because there can be no permanent enmity within the Body of Christ...Matthew 18 again.
But the Body of Christ has no control over the behavior of pagans. Paul could not instruct a pagan to separate, reconcile, and return to the marriage. When the pagan left, he left.
I note that beyond 1 Corinthians 7, Paul insisted that young widows must be married, and all his reasons would apply as well to young divorcees.