Always keep your dream alive.
"Dare to dream. Every failure brings with it the seed of an equivalent success". Napoleon Hill.
So don't be put down by failure, its one step closer to success.
In my career in film especially here in Kenya where it hasn't reached the heights that it has in other parts of the world, I have experienced many low and depressing moments just trying to get by. But with every couple of low moments, they were somehow followed by one major and high moment that overclouded all the low ones. This always kept me going and never giving up through the years to get to where I am now.
Instead of only concentrating on the many low and depressing moments in your life, why not watch out for those few high and uplifting moments that remind you to keep fighting because its all worth it.
Thanks for the inspiration @kiambi