Lenny stooped, and Doreen went flying up on to his shoulder [...] (2.26)
It sounds like assault, but it isn't – it's just the prelude to Lenny and Doreen's hookup. This episode looks ahead to Esther's sexual encounters, which often do not seem distinguishable from violence.
There I went again, building up a glamorous picture of the man who would love me passionately the minute he met me, and all out of a few prosy nothings. (5.26)
Esther's idea of romantic love contrasts with the prevailing view of love around her as something exclusively between husbands and wives, toward the goal of creating a family.
Then he just stood there in front of me and I kept on staring at him. The only thing I could think of was turkey neck and turkey gizzards and I felt very depressed. (6.49)
Ouch. Really, just ouch. Esther is not at all impressed with Buddy's, ahem, family jewels. So much for passionate love.
[Constantin] had what no American man I've ever met has had, and that's intuition. (7.1)
In contrast to Buddy, Constantin attracts Esther because he's got something called "intuition." While Constantin isn't necessarily more attractive than Buddy, Esther feels like she can be honest with Constantin. It helps that Constantin is just as repelled by Mrs. Willard as Esther is.
The main point of the article ["In Defense of Chastity"] was that a man's world is different from a woman's world and a man's emotions are different from a woman's emotions and only marriage can bring the two worlds and the two different sets of emotions together properly [...] This woman lawyer said the best men wanted to be pure for their wives, and even if they weren't pure, they wanted to be the ones to teach their wives about sex. (7.44-5)
This article spells out the prevailing attitude toward sexuality at the time. While it seems to defend chastity, the article actually promotes the idea that the real difference between men and women is that women have to stay pure, and men do not. The best men stay pure, other men aren't, but regardless of whether they're pure or not, all men want virginal wives. Women, on the other hand, have to stay pure no matter what.
Now the one thing this article didn't seem to me to consider was how a girl felt [...] I couldn't stand the idea of a woman having to have a single pure life and a man being able to have a double life, one pure and one not. (7.48)
You said it, sister. As Esther astutely points out, the article mentioned in Quote #5 above doesn't say anything about love. The article makes sexuality sound as if it's just a question of the biological or psychological difference between men and women – there's nothing about love, passion, spiritual connection, romance, or even attraction.
Instead of the world being divided up into Catholics and Protestants or Republics and Democrats or white men and black men or even men and women, I saw the world divided into people who had slept with somebody and people who hadn't, and this seemed the only really significant difference between one person and another.
I thought a spectacular change would come over me when I crossed the boundary line. (7.50-1)
This passage reveals Esther's naiveté about sex. It's not clear exactly what sort of "spectacular change" she was expecting, but it's interesting to see her use the same language about losing her virginity as she does about suicide (see our discussion of this in "Transformation"). In fact, every time Esther seeks a sexual encounter in the novel inevitably ends in her getting hurt.
I began to see why woman-haters could make such fools of women. Woman-haters were like gods: invulnerable and chock-full of power. (9.100)
You can almost predict what's going to happen between Esther and her blind date Marco, the "woman-hater" in the quote above. As with Lenny and Doreen (see Quote #1), consensual sex is indistinguishable from violence, another way for "woman-haters" to assert their power over women. Thankfully, Esther fights back and escapes Marco.
"What does a woman see in a woman that she can't see in a man?"
Doctor Nolan paused. Then she said, "Tenderness." That shut me up. (18.53)
In the novel, Esther seems, well, rather homophobic. The relationship between DeeDee and Joan disgusts her. It's interesting here that Doctor Nolan uses the word "tenderness" because it's exactly the same word that Esther uses to describe Doreen (4.60). It would be a stretch to say Esther is a closet lesbian, but at least Esther learns to appreciate female friendship.
Then the stories of blood-stained bridal sheets and capsules of red ink bestowed on already deflowered brides floated back to me [...] I couldn't possibly be a virgin any more. I smiled into the dark. I felt part of a great tradition. (19.65)
Esther believes that she has undergone the "spectacular change" she expected when she lost her virginity (see Quote #7 above). Instead of being empowered by her experience, however, Esther's sexual encounter leaves her with a dangerous hemorrhage and she needs to be taken to the emergency room, further underscoring the connection between sex and violence in the novel.