I was assigned to make a report on a short story, The Scandal of Father Brown by Gilbert K. Chesterton. The story is about Hypatia Hart, a beautiful daughter of some American magnate. Hypatia Hart has an official husband who is a broker. Tired of her husband she started dating a famous Spanish-American poet Rudel Romanes. I have some problems with understanding the highlighted fragment given below:
The Sob Sisterhood permitted themselves a note of romantic regret; some having even the hardened audacity to quote from the poem of Maud Mueller, to the effect that of all the words of tongue or pen, the saddest are, “It might have been.”
And Mr Agar P. Rock, who hated the Sob Sisterhood with a holy and righteous hatred, said that in this case he thoroughly agreed with Bret Harte’s emendation of the poem: “More sad are those we daily see; it is, but it hadn’t ought to be.”
I can't understand what is meant by “It might have been” and ”it is, but it hadn’t ought to be". Does it mean that
the Sob Sisterhood thinks that the possible marriage between Romanes and Hypatia might have been great, and
that Agar P.Rock thinks that such marriage just hadn't ought to be successful?