“I will learn what everything costs”

following quoted from:
The Cost of Everything, or Why Everyone Should Read George Elliot's Middlemarch

the Finale of Middlemarch:
"The effect of her being on those around her was incalculably diffusive: for the growing good of the world is partly dependent on unhistoric acts; and that things are not no ill with you and me as they might have been, is half owing to the number who lived faithfully a hidden life, and rest in unvisited tombs."
— George Eliot (final lines - Middlemarch)

What Eliot reminds us is that there is a largely invisible web of people, events, and conditions that sustains us, and that for every Wordsworth, there are many more “mute, inglorious Miltons” who “rest in unvisited tombs.”
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No character in Middlemarch, no matter how “minor,” is inconsequential.
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The whole web of society—from Sir James Chettam, and Mr. Brooke, to Bulstrode and the Vincys, to Raffles and the Dagley family of tenant farmers—are interdependent. And that is to say nothing of that great web of history. One individual cannot extract himself from this web, nor one class, nor one race, nation, or epoch, any more than the novelist herself can stand outside of the enormously complex web of history and declare “here, this is how it happened—this is how Rome was founded.”
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All our actions will have far-ranging, unimaginable, and probably unintended consequences. We must try, therefore, to learn, even if imperfectly, what everything costs.
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Dorothea’s voice, as she made this childlike picture of what she would do, might have been almost taken as a proof that she could do it effectively. The searching tenderness of her woman’s tones seemed made for a defence against ready accusers. Lydgate did not stay to think that she was Quixotic; he gave himself up, for the first time in his life, to the exquisite sense of leaning entirely on a generous sympathy, without any check of proud reserve. And he told her everything, from the time when, under the pressure of his difficulties, he unwillingy made his first application to Bulstrode; gradually, in the relief of speaking, getting into a more thorough utterance of what had gone on in his mind—entering fully into the fact that his treatment of the patient was opposed to the dominant practice, into his doubts at the last, his ideal of medical duty, and his uneasy consciousness that the acceptance of the money had made some difference in his private inclination and professional behavior, though not in his fulfillment of any publicly recognized obligation…
As Lydgate rode away, he thought, “This young creature has a heart large enough for the Virgin Mary. She evidently thinks nothing of her own fortune, and would pledge away half her income at once, as if she wanted nothing for herself but a chair to sit in from which she can look down with those clear eyes at the poor mortals who pray to her. She seems to have what I never saw in any woman before—a fountain of friendship towards men—a man can make a friend of her. Casaubon must have raised some heroic hallucination in her. I wonder if she could have any other sort of passion for a man? Ladislaw? --there was certainly an unusual feeling between them. And Casaubon must have had some notion of it. Well--her love might help a man more than her money." Dorothea on her side had immediately formed a plan of relieving Lydgate from his obligations to Bulstrode, which she felt for sure was a part, though small, of the galling pressure he had to bear. (763,768-69)
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Ultimately, Dorothea fails to restore Lydgate’s reputation or improve his marriage. She never knows what a precious gift she has given. This is what true charity is: the left hand does not know what the right hand is doing. But the realist novelist does.
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So that, every semester, and sometimes twice a semester, when I get to Dorothea’s declaration “I will learn what everything costs,” I have to fight back the tears. And it’s not just exhaustion-induced emotion, as it may have been when you marathon readers got there. It strikes me as just about the most romantic—or better, loving—thing one person can say to another. It says that whatever reality throws in our path, whatever constraints, whatever uncertainties, whatever obstacles, I will assume the costs, and do whatever I can to be loyal, decent, and loving towards you. So much better than Will’s earlier declaration to Dorothea “you are a poem!”
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We readers of Middlemarch, “the home epic,” know that “the growing good of the world is half owning to those who lived a hidden life, and rest in unvisited tombs.”