I tell them that Jesus loves them, and that they can NEVER lose their faith, but simply misplace it. You may not have read them yet, but I've written on here about some of my own battles that caused me to misplace my own faith for a long time.. I also refer people to my threads, which are stickied on page 1 of this forum. I've had many people tell me they read my stories and my testimonies on here, and how much I helped and inspired them. That is always humbling to hear, because I don't consider myself to be an inspiration..
I've had alot of people pm me and ask me to pray with them and I've even led a few of them back to Jesus.. that's an awesome feeling and makes me cry every time I do..lol.. and I thank God because he's using me to help these people..