I assume you're a regular around here under a different name, but I'm not going to try to work out who (although I have an idea).

I don't know anything about depression, though I believe the up-and-down state you mention might be what they call manic-depressive. It seems to me that you need to get some proper help, though, if it's affecting your life this much. If you're a kid, maybe you should talk to your parents or a teacher you trust, or some other adult, about getting some proper counselling or advice.

I'm really very wary of relying on the help of people who only know you online. Especially if you're a teenager, because I personally can never tell the difference between suicidal depression and the normal teenage condition. (I'm NOT saying this to belittle your problem, just pointing out that there are some things it's very hard to give advice about without talking in person.) Unqualified support and friendship is certainly something we rinkies can provide any time you need it, though. :-)

I'm pretty sure everybody goes through something bad like this, some time in their life. The important thing is to realise it *can* be sorted out, often more easily than you think. You say that other people have more serious problems -- maybe they do and maybe they don't, but what difference does that make? It's you we all care about. From your description, your problem is serious enough to be causing you great concern. So I really, really recommend that you get some qualified help, soon. You sound very bothered by this and I'd hate to think something bad might happen if you just let it get worse.