Sure thing. Life isn't always easy, and even during the smooth times you can feel utterly like crap. Whether there's things going on, or you've got depression, it's easy to feel like it'd be nice for everything to go away. At least for a while.
I'm not sure if this is the perfect place to discuss this (I don't mind it, but someone might) but you can PM me if this gets locked. It might be a good idea to find out if your family has a history of depression, if you don't know what's going on.
Do you know why you feel the way you do; that is, is it for a reason, or just the way you feel?
In either case, I can see where you're coming from. But it's tough times like these that you can rely on your friends and family, or the good folks here. If you ever feel like talking, even just for idle chit-chat, there's always plenty of people here willing to have a talk.
But in the end, being dead would really accoumplish a whole lot of nothing for yourself, and would be even worse for all those you know and love. Dunno, I'm having trouble trying to put it in to words without sounding cliche or cheesy...
Well, I suppose it'd help to know, if you can say, why it is you feel so down? Don't you just hate it when you don't know why?
But this, too, shall pass. Jus' hang on.