Maybe it turns out she has had some really terrible relationships in the past. (Her one true love is evidently Endymion, who has eternal youth and beauty but NEVER WAKES UP. That seems like an unfortunate choice).
Her dad, Hyperion the god of light, got married to Theia, the goddess of sight - who, was in fact his sister. Keeping it in the family, right? And Theia damn near destroyed the Earth. Sounds like maybe mom and dad might have been a bit of a bad example of relationship dynamics.
She had a brother, Helios, and a sister, Eos. Eos was a nymphomaniac cursed by Aphrodite, which probably would have given Selene a bad opinion of the goddess of love. Helios … good grief. Helios was a philanderer who left most of his sexual conquests pregnant and alone. He provided Selene with plenty of nieces and nephews, and most of them either got screwed over for romantic reasons, or just plain weren’t good people. Pretty much nothing on that side of the family would have given her a positive opinion of love.
But then her folks broke up, and her mom remarried. Step-dad Pallas was a god of war. So, probably always gone on campaign, and of course, somebody who killed people, often and in large numbers, and trained others to do the same. Still, a remarkable improvement over Hyperion, because…
One of the reasons her parents split up may have had something to do with child abuse. Selene bore three daughters (Pandeia, Ersa, and Nemea) by her own grandfather, Zeus. Then she had four daughters (Dike, Eirene, Eunomia, and one who was never even named(!)) by her own brother Helios. So, yeah, with Incest being a family tradition in Helios’ line, Pallas really was a better choice. At least, as far as we can tell, he wasn’t screwing her.
When she met Endymion, she fell in love. But that didn’t work out all that well either. There are several versions of how this next part happened, but they’re all kind of screwed-up. One of the stories is that she put him to sleep forever because otherwise he wouldn’t even let her kiss him. The other version of the story is that he loved her back and wanted to get married, but then the stupid sap went to Olympus to meet his future in-laws, where he fell in love with Hera (who was his wife’s grandmother) and got cursed to eternal sleep by Zeus (his wife’s grandfather, but also Hera’s jealous but notoriously unfaithful husband). Still, however it happened, he went to sleep. Forever. And Selene fell in love with him and had fifty(!) daughters and one son by him. She used to visit him and screw him in his sleep, night after night after night. Which is, you know, just a little bit creepy and can’t possibly have been a healthy relationship. “Rape” is such an ugly word…
We don’t know much about what happened to her fifty daughters, but she had one son by Endymion too. That was Narcissus. Who never really loved anyone except … Narcissus. A bit of a problem child, and yet another shining example of poor relationship skills.
She had one last child though, and this one evidently not by Endymion. And that child? Was the Nemean Lion. We don’t know exactly how she got pregnant with a lion cub, but … “bestiality” is such an ugly word…
Now, I’m just guessing here, but we know she was a good friend of Pasiphae. So she might possibly have gotten the idea from her friend, who had a hobby of going out to her husband’s barn and banging the bulls. I mean, you know, Selene had had a stressful life by that point, and hanging around with friends like that, she might have gotten the idea that a bit of beast would be a good stress reliever.
She was also a friend of the Leukippides sisters, who wound up marrying their kidnappers after the kidnappers killed the guys they loved and had been engaged to. Can you say Stockholm Syndrome?
Now, these are the shining examples of Selene’s life. Is it any wonder that she might curse some folks in some way that guaranteed them abusive relationships?