I hated a book and it was all my fault

I recently read Dorothy Sayers' Gaudy Night, and it was just an awful, teeth-pulling experience, and yet it was probably more about me than about the book. Here's how it felt for me to read the book.

The dean laughed. "Well, we have all been on our toes after last spring's events, of course."
Miss Lydgate flinched. "Surely we don't want to bring up all that again?"
Harriet looked from one to the other, "You're not saying...?"
The bursar interrupted. "Never! Only that if it were to have happened that way, it would surely be a black mark on the school."
Miss Hillyard disagreed; "Only some would take it in that fashion, I'm sure."
The warden bristled. "Miss Hillyard, I'm sure you wouldn't want to offend our guest?" 
Miss de Vine argued that all that was in the past, but Harriet wasn't so sure. 

Now here's my problem as a reader. First, although it seems like there may be seven people in the room, the dean, Miss Lydgate, Harriet, the bursar, Miss Hillyard, the warden, and Miss de Vine, in fact the proper names and the titles are used interchangeably, so that although there are about thirty characters to keep track of, you also have to remember which one is "the fellow" and which is "the scout" and I'm not good at that sort of thing. I needed a chart. 
Furthermore, whatever "last spring's events" and "all that" are were COMPLETELY unclear to me. I had no idea what they were discussing most of the time because they were being so goddamn coy about everything.

She walked along the High Street where she had agreed to meet Peter. Good looking, rich, well-mannered, smart, and loyal Peter. He had asked her to marry him every six months for the last five years, but she obviously couldn't agree to it. There he was, waiting for her at the tea shop. He was prompt, she'd give him that. They strolled to the gardens.
"What a lovely morning, my dear Harriet. Or as the old poet said, 'Lorem ipsum dolor sit amet, consectetur adipiscing elit.'"
She chuckled, and finished for him, "sed do eiusmod tempor incididunt ut labore et dolore magna aliqua."

"Ah, Peter retorted, but 'Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.'"

Harriet blushed, and they turned away from the river. But the thought nagged at her. Why had he, after all, used the present plu-perfect form? What the devil could he mean by it? 

So first of all, it's not at all obvious why she can't marry the guy. In fact, she seems downright hostile to this perfectly pleasant dude. Apparently, the answer is to be found in some previous book, but I'm sure as hell not going to read a bunch of other books to find out. I am too lazy. 

Second, perhaps in 1935 most halfway decently educated people had a passing knowledge of Latin, but that is no longer true. And there was a LOT of Latin in the book. In fact, a pivotal final scene made no damn sense until I Googled it. 

Peter and his nephew, Saint-George, ambled across the courtyard to her. "Well met, my lady," said the lad. "Say, why did the chicken cross the road? To get to the other side!" He amiably nudged her elbow.

Well! If she was going to be treated that way, and publicly, she'd have something to say about it. She penned a strongly-worded letter of rebuke to the boy, and a brief note of apology to Peter. Peter's apology note for the poor behavior of his nephew arrived in the post that afternoon, and he must have sent a strong message to the boy himself, as Saint-George's profuse apology came by courier after the dinner hour. 

Seriously, this is why I can't read Jane Austen, Henry James, etc. Someone is always getting wildly offended at someone's act or remark and, because I have so little understanding of the social mores of the day, I have NO IDEA why.  I remember in one of the books I read for college, a girl was being courted by a guy, they went to a dance (with permission), they danced, and the next day the family was ready to leave the country and burn the house down in embarrassment over the damage done to her reputation. I had to ask the professor what the hell happened. (If you're wondering, too, the chaperone had to take home a sick kid, so she was unchaperoned, even though she didn't know it.) Anyway, I know that's the way it was back then, but it's insanely stupid, and I can't get past my modern sensibility to pretend otherwise. I'm making up the sections above, obviously, but there was seriously a scene where the kid told a joke and a flurry of apology letters and rebukes were sent around over how badly Harriet had been treated. I still have no idea what happened that was so offensive.

Anyway, I hated the book, not because it was a bad book, but because I can't keep track of so many characters (and their various titles), because I don't know Latin, and because I have very little understanding of (or patience for) the stuffy politesse of the time period.