Giving till we take
What if your best friend told you the following:
"I have a secret that I want to share with you because you are my best friend in the whole world. I have never revealed this to anyone. There is a forest at the end of the city. You need to go at night, so no one sees you. If you go through the bushes and trees, and brave the thorns, and forge a path through the forest for a few difficult hours, you will come to a clearing. If you dig in that clearing, you will find a treasure of gold coins that I put there for you, worth millions of dollars. This will be more than enough money for you to live comfortably for the rest of your life. (I had to hide it in that place, so no one else will steal it.)"
So you start out on the journey, and it starts raining, and you are scared and wet, and it's dark, and you get scratched by the thorns and you're tired and weary... But you press on... Do you start cursing out your friend for being "selfish"? Of course not! You understand what an amazing friend you have who wants you to live in comfort for the rest of your life! What is a few hours of struggle and pain compared to the rest of your life? Look what a treasure your friend hid there for you!
So think about it. This short life of 80-90 years, compared to ETERNITY. Hashem has revealed to us in the Torah the secret to everlasting LIFE and JOY. If we just press on and trust that we are on the right path, and we trust that He truly is our best friend Who means ONLY our good, then we can make this difficult journey with JOY in SPITE of the pain.