This is a tough challenge. There are so many moments(some of them taking years to fully understand) that have changed my life. i.e Desiderata.
The one I will share here is the night I did not commit suicide.
After years of drug addiction everything that I had valued was lost. Family, money, reputation and most importantly self respect. I had reached a point described as "incomprehensible demoralization".
It's a place you can't really describe. After 30 yrs I can still feel what it was like. Imagine everything that means anything to you is gone. GONE.
The only thing left was a mess. Everything broken. No hope.
I had been a happy, optimistic person my whole life. Life always worked out. I noticed beautiful sunrises, the aspen glow on snow covered mountains, watching my children. I still, to this day watch my kids, although grown adults, with amazement.

Incomprehensibly demoralized is where I found myself.......
A solution came to me....
A rifle...an end. It was an actual option, something I could have never before or since been able to entertain.
I felt another option at almost the same instant. God.
God was in the room with me. Had been the whole time. My whole life I realized he had been right there.
I kneeled at the couch and prayed. He accepted me. Just as I was at that moment. The worst I had, and he accepted me. The grace that was offered had nothing to do with my behavior. Good or bad. It was bigger than my efforts and failures.
Humility is what I gained that night. I won't be perfect. I don't have to be. So good things I do now, I do out of love. Love and acceptance God gave me at my worst.