No after an experence like this one people usally stay togehter and they'll probably become friends.

I think that they will either stay together or not talk to each other at all. On one hand, this awful experience may have cemented their friendship after going through it together. Or they might have felt so bad about doing it that they think it's best to not bring it up again. Therefore, they wouldn't really have anything to talk about so they wouldn't speak to each other at all.

This is a really good question. Actually, I was wondering if they were really ever even friends in the first place. It may be true that the only relationship they have exists b/c they are all taking the same class. Hmmmmm.... People that suffer tragedy together do tend to end up forming very close relationships (there are lots of stories about plane crash survivors marrying each other), but I wouldn't really say that they are suffering a tragedy together. This may have the opposite effect. Good question; I don't know....