Rebelson that is the fear I have for my son as well.
He almost died and still doesn't seem to get it. He has another week of limited contact but after that we'll see how he acts. If he isn't in it with both feet I will have very little contact with him. I get too close to him and I get burned. I have (self-diagnosed but I'm sure it's it) IBS from him already and feel like I'll get cancer someday from all the stress I've had to endure. We all know it does not manifest itself well and it's hard on our bodies. We are so close but this addiction has just made it impossible for me to continue this for MYSELF.
I hope that your therapist can help you deal with all of this so you can be whole for yourself and your younger children. 
