I was once asked by a student at a reTHINK Apologetics conference how he could gain the courage and confidence he needed to talk to his druggie friend - who is so far away from God - about Christ.
You might have a few friends who seem ridiculously far away from Christ - friends you despair of ever reaching - but I have good news for you: Your spiritually hopeless friend is no farther away from Christ than any of your other lost friends. They are all “dead in their trespasses and sins” (Eph. 2:1-10), and there’s only one kind of dead. Dead is dead. The good news is that God is as able to open the eyes of your seemingly-most-resistant friend as He is able to open the eyes of any other friend, so you need not shrink back because of any thought that your friend’s rebellion against God is too great.
The root difference between believers and non-believers is spiritual, and spiritual death can only be reversed by the God who “gives life to the dead and calls into being that which does not exist.” Granted, He does this through the means of our evangelism. Our words explaining the gospel (including words explaining that the gospel is true, an accurate description of reality - i.e., apologetics) are the means God uses to change people’s hearts and call them to Himself, enabling them to see and love Him.
But our evangelism is only the means. He is the cause of any success we see, and that is what frees us from fear. Your friend’s salvation looks impossible? Well, good news! “With people this is impossible, but with God all things are possible” (Matt. 19:25-26). If even the most hardened criminal comes to Christ in the same way as your dear grandmother - by a miracle of God - then you can be as hopeful and fearless in talking to a hardened criminal as you can in talking to your grandmother.