Boy do I understand how you feel, sadly I have been where you are, and am there quite a lot, but things get better. Right now you may feel like crawling into a hole somewhere and never coming out, but that's when you need to try hardest to stay out in the open, you need to try to remain connected. All hiding and doing nothing accomplishes is making you more depressed, and here I am speaking from experience. You will make it through, you are strong enough to get through this until better days emerge from the darkness of depression that you are in right now.
I like to compare it to the saying "there is not enough darness in the world to cover the light from a single candle" I like to think that no matter haow many depressed days there are, they can never overcome even one good day. May sound a little corny, but I have to believe things get better, not only for me, but for you also.
Impossible is just a big word thrown around by small men who find it easier to live in the world they've been given than to explore the power they have to change it. Impossible in not a declaration, it's a dare.