I'm willing to accept sounding like an asshole, but I certainly don't think I need to say nothing, and in fact you telling me so makes me think that of you. And not that you sound like one.
I find it's best to discuss problems before they become a pattern. Not to mention, this is a pattern. There was a whole similar (though far less urgent and interesting) thread from Zed Shaw that had a few top posts here before. There was the dude from Justin.tv, which at least you could argue was relevant due to that startup's affiliation with YC. I'd bet there were others I've missed or can't remember.
The problem is, of course, that these sorts of stories could overrun every social news site with ease, especially given that each one will lead to multiple posts. Every time someone says "I'm going to commit suicide" dozens of people on each site will think "Hey, I can help find this guy by posting to HN/Digg/Reddit or upvoting." And since saying you're going to commit suicide is clearly a cry for help (those serious about it just do it) and it clearly gets attention, there will be a torrent of these. Each one will be followed by at least one or two updates too.
I feel like there's some game theory there. You can decide to allow them all, in which case you're encouraging them, which will in turn make the web suicide threats (and other urgent stories) increase, until they're a huge problem. Or you can just delete them all and decide that while we all want to help those people, this just isn't the proper venue, and that having those things here probably hurts the mentally ill people they're meant to help in the first place.