Wow, I just read your thread and I felt like I was reading something that I wrote myself. I share the same exact story. I can't believe how similar it is to my situation. Like you were saying sometimes you don't even know you are doing the picking. My husband has like walked into a room where I am sitting there on the computer, watching tv, or reading as has said "stop picking" and I realize that I didn't even notice I was doing it. Also with the scratching all over my whole body, once I start in one area it moves to another area and by the time I know it my whole body is red and irritated. I at first started picking a few zits on my face and now I do it all the time just like you said in the different areas and stuff. I is pretty bad because I start on one spot and pick it so much then it scabs up and I just keep picking the scab off and then more zits appear and so on.
I have recently started going to group and individual therapy for other issues but now that I have read this story of yours and noticed that I am not alone, I think I may mention it to my therapist because I suffer from anxiety, social phobia and low self esteem and this issue may be adding to this phobia's. I am sorry that you are going through this, I know how you feel. I just want to stop and I am sure you do to. It is comforting to read that someone else knows what I am talking about, because my husband doesn't understand and that is why I try to hide it from him with makeup and it takes so long to cover all the spots on my body.