I think I agree with Vicky about the email. My sit is not a cover all--things were a bit different for me. I will say this, and I hope it's not taken the wrong way, but if you do go dark make that include times with your daughter. Don't let him have any family times (that is if you are). Let him know what it's like to really lose you. But, I still say stop the D. Without a doubt.
I'm sorry if I can't be more helpful. Keep praying and keep the faith. Also, look to see what God is trying to teach you through all of this.