What annoys me most, is that a lot of readers *did* pick up on the abusive-boyfriend-means-he-loves-me plot/subtext. I'm on the BDSM scene, and there has been an influx of teenage girls (16 being the age of consent in my country, for reference, but they are mostly around the 18-mark in order to get into the fetish clubs) who want to be "beaten" so they can feel loved. People in the community realise that these girls have no idea what they are on about, have misconceptions about BDSM in general, and worse still - know that there are unscrupulous types out there. Which means that these girls are putting themselves into potentially dangerous situations as they have no idea what they are doing and what someone to treat them like Edward does Bella - after all, that is how true love works, right? Will they listen to any advice, either about BDSM or safety? No, because people are just prejudiced about the books as they will never be as popular as Bella/Edward...
One could argue that "I hate it because it is popular". Indeed I do - because Meyer makes a staggering amount of money from the books/films' popularity, and donates a significant portion of her income to the Mormon church, which in turn uses the money to fund anti-gay rights and anti-abortion movements within the United States.
That is aside from the domestic violence subtext itself (Oh, it's ok that he beat her black and blue, he loves her really!), the stalker nature, the Mormon and American-Conservative values it is trying to imprint, that women should be dependant on men, the general atrocious writing and characterisation, and what it has done to both vampire lore, and the prevalence of Twilight-related merchandise in any sort of alternative/Gothic/geek/book shop, and so on.