What everyone else said ... in spades, and twice over.
You wanna know a 'secret' though dude? Staying clean/sober really comes down to a few simple principles. You can learn these principles at NA/AA, as well as some secular programs. Because your mind is strung out at this moment, and you're all depressed and craving ... it probably all seems impossible right now. But it's not ... staying clean is just about learning to control what you think about, and controlling the internal messages you send yourself. You CAN learn how to do this, anyone can. But it cannot begin until you suffer through the w/d's and get your head straight.
Good luck out there. Try not to drag this out too long, or you WILL end up in a HUGE WORLD of friggin hurt.