He's just fishing around for attention right now. Don't bite.
As for exposing, personally I don't know how much good it will do. If he has the addictive compulsions like you've descibed, he's just going to do it again or strengthen his bond to the OW.
It seems like ignoring him is getting you more of a response than anything else. Stay strong and don't respond to him. If you need to respond to him, just answer with yes...no type answers.
M-43 W-40 2D - 9 and 5
Emotion, yet peace. Ignorance, yet knowledge. Passion, yet serenity. Chaos, yet harmony. Death, yet a new life.