I have prayed for you and will continue to pray for your situation.
 I am so sorry that you are going through such difficult time. You are wise in deciding to talk to your son in love, I pray that the Lord will give you the words to say. It is a very painful thing when  one`s own beloved child, having being brought up in the faith, gets led in the wrong direction. The only thing we can do is give our children to Jesus and He will sort it all out for His glory. It may be painful to watch. Your son might have to reach a dark place before he is rescued, but the Lord is in control, He will do what He has promised to do, He will never leave nor forake us. The Lord has a plan for your son, all you have to do now is to trust Jesus in this situation and rest in the Lord, putting aside all anxiety.
 
This comes to you both with much love
 
Jane