Actually I say it as: "Money doesn't buy happiness. It buys the yacht and you sail there."
As someone without two nickels to scratch together I can say the poor part isn't fun. I would like to try the rich part just to be sure.
Maybe the one leads to the other. When one is not doing well there's a tendency to think that if they were doing well they would be happy. Wrong! I think you can get there from there though. Seems like there is a major readjustment that has to take place to recognize that happiness is about wanting what you have rather than having what you want. The world is full of stories of people who worked their tails off to get money only to find they were miserable once they got it. After all, the root of miserable is miser.
What part of your life are you in? The reason I ask is that we've all been there, brother. If you are in your twenties or early 30s, you may still be struggling.
Your earthly reward will come later, if that is the case. I say that as someone who once was a poor veteran without two nickels to rub together, back in 1970. Now I'm richer than I ever dreamed I'd be, just by working hard and putting money away in a 401K (my wife also worked and had a 401K, so that adds to it).
I wish you happiness and prosperity. Don't lose faith. It may take your adult lifetime, but stay on the right path and it will come.