If there was anything even lower than the Underworld, it was Demeter's opinion of Hades, and if there was anything lower than that, it was Hades' opinion of Demeter. Her hatred of the Underworld and anything that wasn't lush or green meant that Hades hadn't ever meshed well with her as his sister. As his mother-in-law, she had become unbearable. Ironically, the only thing that really stopped Hades from executing his finely tuned revenge fantasies was that position.
The end of Hera's response, however, annoyed Hades, as much as it relieved him. He was still sorry that the decision to not see Hera had hurt her, but now he knew with perfect certainty that it had been the right thing to do. She wouldn't have let him marry Persephone? Let? As if she were his mother, and he had to follow her every whim. Hades wouldn't even entertain the whims of their actual mother if she asked. That was the responsibility of the golden son, and when that one wasn't available, the silver.
Hades made his own decisions. He had always made his own decisions. They didn't always turn out to be the right decisions, or the best decisions, or even good decisions, but they were his decisions. Hera could disagree with them all she wanted. She could vocalize how much she disagreed with them all she wanted. She could do everything in her power to make him change his mind. But meddling was where Hades drew the line. Things would have turned out so much worse if Hera had known soon enough to interfere.
“I would have been honored that you offered your daughter, but I would have refused it,” Hades said. “Marrying for the sake of marrying or even finding a queen was never my aim. If it were, I would have married a goddess from the Underworld."
Before Persephone, Hades had never intended to marry. There were a few goddesses in his realm that he thought would make excellent queens, but he'd never felt inclined to pursue anything. It wasn't that he had something against the practice. Hades thought that it was a very lovely idea. For other people. But Hades knew if he pursued, he might fall in love. Emotions created biases, and clouded judgment. He had an Underworld to run, and the Underworld deserved the best ruler possible. The best ruler of the Underworld was one with some mercy, but no heart. Put a queen in the equation, and Hades risked becoming warmer, and even worse, the queen risked becoming cold. Someone who grew up in the Underworld might go unchanged, but an Olympian who grew up in a shiny bright palace that close to the sun didn't stand a chance.
Hades paused, then added gently, "I don't know that you would truly wish that adjustment on your daughter if you fully understood what it entailed.”
Sometimes during the winter months, Hades would look at Persephone sitting next to him in the court, with her eyes grimly fixed ahead and her posture like stone, and he'd remember the way the sun had bounced off her hair and the tips of her fingernails when Hades first saw her. Then the same thought would inevitably occur to him. If Hades had truly cared about her, if he'd truly cared for her at all, he would have left her in the light.