Basically, my biggest gripe with emo is how it belittles such a mental illness and turns it into little more than fashion.
Anecdotal evidence time:
I have two friends that are "emo". Case 1 can be called "Bob" and Case 2 can be called "Rob".
Bob is a dude I have known since my second year of high school. He was a good humoured, energetic dude and pretty well adjusted. Fast forward a few years and the change is pretty immense. I'm not even talking about losing some traits to gain others, I'm talking about a massive change. He's become really apathetic to everything. It pisses me off, because I'm trying to communicate and be friendly and all he seems capable of is responding in a disinterested, monotone voice that more or less says, "I am too good for you".
So basically Bob uses the "emo" scene as a platform for elitism.
Rob is much more friendly and stuff! I like him a lot better, because he's still fun to hang around and we get along really well. The thing is, though, he glamourises depression and suicide pretty heavily. He can't resist an opportunity to point out that he attempted suicide (can't confirm this), only ever sees death in his dreams (fat chance) and rolls up his sleeves a day after cutting himself so everyone can see. I am really not sure what Rob is trying to communicate here. That he is emo? Success, then.
Would I be fair in saying that members of the "emo" subculture generally use it as a means of confused subconscious expression with little conscious idea of what they're doing? Or am I full of shit?