God's Plan of Happiness Mormon.org: "“Where did I come from and why?”
It’s hard to move forward when you don’t know where you’re headed or why. God’s plan gives us the answers to life’s most basic questions like, “Where did I come from?” “What’s my purpose here?” And, “What happens when I die?” Knowing the answers gives us hope and helps us find peace and joy.
Your life didn’t begin at birth and it won’t end at death. Before you came to earth, your spirit lived with Heavenly Father who created you. You knew Him, and He knew and loved you. It was a happy time during which you were taught God’s plan of happiness and the path to true joy. But just as most of us leave our home and parents when we grow up, God knew you needed to do the same. He knew you couldn’t progress unless you left for a while. So he allowed you to come to earth to experience the joy—as well as pain—of a physical body.
One thing that makes this life so hard sometimes is that we’re out of God’s physical presence. Not only that, but we can’t remember our pre-earth life which means we have to operate by faith rather than sight. God didn’t say it would be easy, but He promised His spirit would be there when we needed Him. Even though it feels like it sometimes, we’re not alone in our journey."