Back to Middlemarch. Because 15 posts isn't enough.
1/ Reviews and blog posts about Middlemarch often ignore the Mary- Fred plot. It is important, especially when we remember that George Eliot's a didactic author, a sort of sage writer. That plot is there to make a point, and to contrast with the 2 1st plots.
In Anna Karenina, there are 3 families: Anna- Karenin (-Vronsky), Levin- Kitty and Dolly- Oblonsky. Tolstoy depicts them to demonstrate the 1st line about happy and unhappy families (in the 1st one, both husband and wife are unhappy; 2nd one, husband and wife are happy; 3rd one, husband's happy, wife's unhappy, but the 3rd marriage should be regarded as another kind of unhappy family) and to depict 2 kinds of love- romantic/ passionate love (Anna- Vronsky) and intimate love (Kitty- Levin), and ultimately to argue what constitutes happiness.
Similarly in Middlemarch, there are 3 main couples: Dorothea- Casaubon, Lydgate- Rosamond and Mary- Fred. We may say that by depicting and analysing them, George Eliot helps demonstrating the 1st line of Anna Karenina and offering 2 other forms of unhappy families. The marriage between Fred Vincy and Mary Garth doesn't take place till the end, but throughout the novel George Eliot writes about their bond and the impact they have on each other (though it's mostly Mary's influence on Fred) and some necessary components for future happiness. Placed next to this couple are 2 other happy families, Sir James- Celia and Mr and Mrs Garth, which are also built on love, understanding, compatibility... (I admit that it's a guess regarding Sir James- Celia, as their marriage's not described in many details, but I think we can say so because they are compatible and harmonious, having similar values and similar thoughts on many subjects, such as Casaubon, Will Ladislaw, the will...).
It should be noted that there are 2 other marriages at the end of Middlemarch. Rosamond's 2nd marriage, after Lydgate's death, is unimportant and can be skipped. That Dorothea marries Will may not satisfy everybody (because he's irresolute or, to some people, inferior to her), and on my part I find Will not very fully developed as a character, but George Eliot does take care to let them have the necessary factors for a happy marriage that are absent in Dorothea's former marriage, such as compatibility (similar thoughts, values, aspirations...), love, trust, understanding, mutual respect and openness.
2/ I've seen readers who express regret that Dorothea doesn't marry Lydgate instead. The heroine and the hero of the book, they say. I don't think that's a good idea. Lydgate's unlikely to let Dorothea have freedom to learn and do what she wants, he's unlikely to talk openly to her about his work or to let her help in any way except by spending her money on the hospital. They're different people, with different interests. At the same time, mixed with Lydgate's wish to do good to people in the community is a sort of egotism, an ambitious to succeed, do something important and become known.
Those critics, I'm afraid, don't see these characters as clearly as George Eliot sees them. A man like Lydgate is unlikely to fall in love with a woman like Dorothea. He may admire her, he may be friends with her, but cannot fall in love with her.
3/ Come to think of it, Middlemarch is more melancholy than the early Adam Bede and George Eliot's last novel Daniel Deronda. It's full of fools, egotists, philistines. It's full of disappointments. Dorothea and Lydgate, the 2 people that yearn for something better, higher, find their dreams and aspirations thwarted. Casaubon spends his whole life doing research on a book that is never begun. Farebrother chooses a wrong vocation. The Vincys are disappointed with their children's marriages. And so on and so forth.
It would be as sad, melancholy and pessimistic as Flaubert's Sentimental Education, if not for the Garths, who are there to function as the moral touchstone or moral centre of the book and to balance out or reduce the negativity in the tone. The Garths, specifically Mr Caleb Garth, Mrs Garth and Mary Garth, are at peace with the world, because they do their duties, live honestly and kindly, and do nothing that gives them a heavy conscience. However, I don't think that George Eliot wants to say that people should be content with what they have, forget ambitions and yearn for nothing more, because Dorothea and Lydgate fail not only because they have big dreams, not only because they're hindered by society, but also because they have weaknesses of their own. Regarding Lydgate, he makes a mistake in choosing a wife, but there are also faults in his character- his attitude towards women, his weakness, and his pride (it's because of pride that he feels guilty and yields whenever Rosamond talks of her disappointment, which means he fails as a husband). Regarding Dorothea, I'm afraid that some readers idealise her too much (in the essay "Why Feminist Critics Are Angry with George Eliot", Zelda Austen says that some feminists criticise George Eliot for not allowing Dorothea to do what the author did in real life). Dorothea is not George Eliot. There's no indication that she possesses the same mental abilities and vast knowledge- I doubt that she does, growing up with a scatter-brained uncle like Mr Brooke. She lacks wit, and wisdom, Leslie Stephen is right to say that she even has "a slight touch of stupidity". Not only does Dorothea go against everybody and marry a man like Casaubon, asking herself whether she deserves him but not whether he deserves her, but she also shows insensitivity or foolishness in making the same mistake twice- at the beginning, she fails to realise that Sir James is courting her, thinking that he loves Celia, later, she believes that Will's having an affair with Rosamond. In addition, she takes a long time to realise that she herself has feelings for him.
4/ Actually, it's not incomprehensible that the 3rd plot is ignored. Mary Garth and Fred Vincy are not as complex, interesting and fully developed as Casaubon, Rosamond, Lydgate and Dorothea. Their love story is unremarkable in itself, and wouldn't be fascinating as an independent book. It simply has a function. Apparently, the plot of 2 young people improving themselves to deserve each other and deserve happiness is Jane Austen's thing.
Now, having written and published this post, I'll go to a wedding.