and these are some of Damon and Stefan's lines from that episode:
[Remember Elena fed Stefan some of her blood in 1x17 and at the end of the episode, Damon found Stefan in his room surrounded by a few empty blood bags, and looking terribly guilty.]
At the Boarding House:
Damon: How long did it take to wean yourself off of it after you last indulged?
...
There's nothing wrong with partaking in a healthy diet of human blood from a blood bank. You're not actually killing anyone.
Stefan: I have my reasons.
Damon: What are those holier-than-thou reasons? You know, we've never actually discussed that. You know, I'd love to hear this story.
At Lockwood Manor:
Damon: We are who we are, Stefan. Pretending doesn't change that.
I've been exploring this in my Big_Fang, and I was already pretty convinced, but this made me more certain: Damon has NO IDEA about that migrant village. And Stefan, who is in denial about his true nature, never told his brother any of it--out of shame, for sure, though I'm sure in general he didn't want Damon to know his weakness was so extreme. Although, can't you just see Damon asking, "Why didn't you ever tell me?" because it actually might have HELPED. Gah.
OMG, I WAS JUST GOING TO LINK UP SOME PRETTY PICTURE OF IAN SOMERHALDER AND PHOTOBUCKET IS ALL MESSED UP! THE PHOTOS I'VE PREVIOUSLY LINKED APPEAR TO BE FINE, BUT IT'S LIKE I CAN'T GET TO MY ALBUMS. IS ANYONE ELSE HAVING THIS PROBLEM?
All is right in the world again, no worries!