3 mothers who abandon their babies

Of the 6 novels I've read over the past few months (Shirley, Daniel Deronda, The Moonstone, Despair, Jazz, Strange Case of Dr Jekyll and Mr Hyde), 3 have a mother that abandons her child.
In Daniel Deronda, after many years Princess Leonora meets her son Daniel Deronda, gives him the answers. There are 2 main reasons: 1 is that as a Jew she believes it's better to let her son have an English upbringing and become an English gentleman, away from Judaism and the Jews and all the negative things associated with Jews ("I relieved you from the bondage of having been born a Jew", "I chose for you what I would have chosen for myself"...), the other is that she cannot be a mother ("I had not much affection to give you. I did not want affection. I had been stifled with it", "I wanted to live out the life that was in me, and not to be hampered with other lives", "I did not want a child", "I did not want to marry [...] I had a right to be free", "I will not pretend to love where I have no love"...)
We may not agree with her decision to conceal from Daniel his identity and heritage, we may not approve of her hatred of being Jewish, we may find her too cold, selfish and cruel, but somehow her thoughts and actions are understandable and therefore acceptable. Especially when we consider that Daniel gladly accepts and embraces his own Jewishness because he himself wishes it, due to Mirah and Mordecai, mostly Mirah, a different man under these circumstances is not likely to condemn the Princess and resent her decision as strongly as Daniel does.
In Jazz, we don't know why. But we know something's not right with Wild.
"In the trees to his left, he sees a naked berry-black woman. She is covered with mud and leaves are in her hair. Her eyes are large and terrible. As soon as she sees him, he starts then turns suddenly to run, but in turning before she looks away she knocks her head against the tree she has been leaning against. Her terror is so great her body flees before her eyes are ready to find the route of escape. The blow blocks her out and down."
That encounter between her and Golden Gray is the 1st time we see Wild. Golden Gray picks her up, tries to save her, brings her to the place of Hunters Hunter, then she gives birth. The kid is probably Joe Trace, we don't know for sure, but Joe assumes so, and we may believe so. That is a different story, however- to get back to Wild, she never speaks a word. The 1st thing she does when waking up is to bite Hunters' Hunter. Nuts.
Look at this:
"She lived close, they said, not way off in the woods or even down in the riverbed, but somewhere in that cane field- at its edge some said or maybe moving around in it. Close. Cutting cane could get frenzied sometimes when young men got the feeling she was just yonder, hiding, and probably looking at them."
And then this:
"The cane field where Wild hid, or watched, or laughed out loud, or stayed quite burned for months. [...] Would she know? he wondered. Would she understand that fire was not light or flowers moving toward her, or flying golden hair? That if you tried to kiss it, it would swallow your breath away?"
Wild never speaks a word, not even once. I'm not sure if she does speak. It's not simply that there's no direct quote, but there's no indication of her saying anything either. A short while after having her baby, she goes away, probably into the woods, followed by Golden Gray. And never comes back for her kid (if she's indeed Joe's mother, that is). Joe asks questions, and Hunters Hunter says "She got reasons. Even if she crazy. Crazy people got reasons."
Then it kind of makes sense. She's crazy! 
(Toni Morrison clarifies it for us: "a simple-minded woman too silly to beg for a living. Too brain-blased to do what they meanest sow managed: nurse what she birthed. The small children believed she was a witch, but they were wrong. This creature hadn't the intelligence to be a witch. She was powerless, invisible, wastefully daft.")
And then in Shirley, we find another mother letting go of her child. Let's hear what Mrs Pryor says to Caroline: 
"I had reason to dread a fair outside, to mistrust a popular bearing, to shudder before distinction, grace, and courtesy. Beauty and affability had come in my way when I was recluse, desolate, young, and ignorant—a toil-worn governess perishing of uncheered labour, breaking down before her time. These, Caroline, when they smiled on me, I mistook for angels. I followed them home; and when into their hands I had given without reserve my whole chance of future happiness, it was my lot to witness a transfiguration on the domestic hearth—to see the white mask lifted, the bright disguise put away, and opposite me sat down— O God, I have suffered!" 
And:
"I let you go as a babe, because you were pretty, and I feared your loveliness, deeming it the stamp of perversity. They sent me your portrait, taken at eight years old; that portrait confirmed my fears. Had it shown me a sunburnt little rustic—a heavy, blunt-featured, commonplace child—I should have hastened to claim you; but there, under the silver paper, I saw blooming the delicacy of an aristocratic flower—'little lady' was written on every trait. I had too recently crawled from under the yoke of the fine gentleman—escaped galled, crushed, paralyzed, dying—to dare to encounter his still finer and most fairy-like representative. My sweet little lady overwhelmed me with dismay; her air of native elegance froze my very marrow. In my experience I had not met with truth, modesty, good principle as the concomitants of beauty. A form so straight and fine, I argued, must conceal a mind warped and cruel. I had little faith in the power of education to rectify such a mind; or rather, I entirely misdoubted my own ability to influence it. Caroline, I dared not undertake to rear you. I resolved to leave you in your uncle's hands." 
What? 
I know Mrs Pryor has a hard life, full of suffering, as a governess, and as a wife. I know hardships and experiences with unpleasant people make her pessimistic, cynical, to some extent misanthropic. I understand that sometimes a woman extends the loathing of her husband to their child. But "I let you go as a babe, because you were pretty, and I feared your loveliness"? To quote G. H. Lewes: "Really this is midsummer madness!"