There are other factors I remember, like:
* Rachel self-mutilated herself in front of everyone after being egged by Jesse
* Mike's parents were abusive
* Mike, Kurt and Matt had some kind of threesome relationship.
* Quinn's story was that she did get pregnant, her parents kicked her out, she moved in with Finn and Carole despite the baby not being his. She was going to tell him, but then they got in a car accident. Finn and Carole both died, and Quinn lost the baby, who she mentally named "Caroline."
* The last bit of the story was Mercedes squeezing Quinn's hand through her coma.
And I have a feeling like the title had something to do with winter. *shrug*