Hang in there! You are resilient. Say that over and over. My impression from your letter is that the progress you made with these men in one day is not to be underestimated. I keep this poem by my desk when I"m feeling particularly doomed and frustrated by the forces at hand. I"m not religious either, but I find great solace int his piece.

Do it, anyway

People are often unreasonable, illogical, and self-cantered;
Forgive them anyway.
If you are kind, people may accuse you of selfish, ulterior motives;
Be kind anyway.
If you are successful, you will win some false friends and some true enemies;
Succeed anyway.
If you are honest and frank, people may cheat you;
Be honest and frank anyway.
What you spend years building, someone could destroy overnight;
Build anyway.
If you find serenity and happiness, they may be jealous;
Be happy anyway.
The good you do today, people will often forget tomorrow;
Do good anyway.
Give the world the best you have, and it may never be enough;
Give the world the best you've got anyway.
You see, in the final analysis,
it is between you and God;
It was never between you and them anyway

— Mother Theresa