I’m thankful for your concern for this person, and I hope you’ll continue to pray for him and to share Christ with him, as God gives you opportunities. The Bible says, “Be wise in the way you act toward outsiders; make the most of every opportunity. Let your conversation be always full of grace” (Colossians 4:5-6).
People reject Christ or don’t want anything to do with God for many reasons, and sometimes it’s helpful to pinpoint these. Some, for example, turn away from God out of pride; they don’t want to admit they have messed up their lives (to use your term), or that they need God’s help. Others turn away because they don’t think He cares about them or wants to help them. Still others turn away because they’ve been turned off by someone who claimed to be a Christian, but didn’t live like one.
But whatever the reason, God still loves them, and Christ wants to forgive them and help them—even if they don’t believe it right now. This is why the most important thing you can do is to pray for this person, because only God can convict him of his sin and open his eyes to His truth.
Then ask God to help you be an example to him of Christ’s love and peace and patience. As I’ve often said, people may doubt what we say, but they can’t deny the reality of a life that’s been touched by Christ.