Have you ever asked yourself why you have a hard time believing in God? One reason, I suspect, is because you are trying to talk yourself into believing in Him—and yet you don't have any reason for believing He exists.
Is there any evidence for God? The answer is Yes! For one thing, God has left His "footprints" all around us. After all, isn't it more logical to believe that God created this world, than to think it all happened by chance? The psalmist's words are true: "The heavens declare the glory of God; the skies proclaim the work of his hands" (Psalm 19:1).
But the Bible points us to an even greater truth: We can know God is real and that He loves us, because He became a man. This man was Jesus Christ. Do you want to know what God is like? Look at Jesus Christ, for He alone "is the image of the invisible God" (Colossians 1:15). He proved this by dying for our sins on the cross and then being raised from the dead by the power of God.
Your letter reminds me in some ways of one of Jesus' disciples who still found it hard to believe. His name was Thomas, and although others told him Jesus had been raised from the dead, he still refused to believe. But then Thomas met Christ personally, and immediately his doubts vanished and he exclaimed, "My Lord and my God" (John 20:28). This can be your experience if you will turn to Christ and ask Him to come into your life.