That was explained
Yeah, it's always "explained". Doesn't change the fact that it happened.
It's a 14-yr old girl fantasy - a mysterious guy turns up at high school and he's a bit dangerous but he's good really. And then he goes a bit bad, but the child's love for him prevails and he becomes good again. Blah, blah, blah. And he has hair which sticks up a lot, and is a bit moody and boring.
Buffy, Twilight, TVD, etc...
At least Buffy didn't take itself too seriously. TVD is so solemn about it. It's a parody of teenage vampire stuff, but thinks it's drama.
I echo True Blood and Being Human as superior shows. Well, superior shows for adults. I'm sure TVD and Twilight etc. are exactly right for their demographic.
Vampire Diaries? Sorry, man - you'll never get me to say it's anything but really dire TV.