Deaths aren't as meaningful as they were before.
I know tons of people on the forums complained that Nick and Sarah died. Especially how they died, it bothered me a little also. Sarah's death made a lot of people mad that she ended up dying even when you save her, especially since she actually seemed like she wanted to learn, and then nobody seemed to care it was just "Hey look a baby!" Nicks death the music seemed off and it wasn't upsetting at all, and Clementine wasn't that sad.
2+ years in the apocalypse and people aren't going to be emotional as they were at the beginning when somebody died. It's like what Vernon said when Brie died, seeing someone die used to bother him but now he doesn't feel, he takes it in stride. So it's not like people are going to get emotional and break down crying when someone in the group dies anymore. I'm excluding Rebecca since she had tons of hormones from her pregnancy.
What did annoy me is that Luke seemed more bothered by the fact that Jane left, a girl he just met compared to his best friend of 20 something years ending up dead.