> But I don't want to see the frontpage filled with articles about suicide, depression, and celebrity gossip -- that's not what I'm looking to read when I get on HN! And I assumed that others felt as I did, so seeing this upvoted to #2 on the frontpage, I was a bit shocked that my assumptions had been violated.

So flag it. if others agree with you, they will too. If they don't, maybe it is not really your culture, then? It is just an online forum; there will be others.