Scalp & Ear Picking

I'm sooo relieved to find I'm not the only one! I was sitting and my computer, peeling skin off my head, and decided to google it just to see what came up... and here I am. I've had psoriasis for about ten years, maybe just under, and during that time I have picked non-stop. It's on my scalp, behind and inside my ears, and on my forehead against my hairline. Usually there's no trigger or anything that makes me start. I just find my hand creeping up and feeling for the dry, rough skin. I rip it off in patches, sometimes these pieces of skin being over an inch long. If I've recently picked and it hasn't had time to heal, I'll just scratch until my shoulders and hair are covered in bits of white skin like dandruff. The thing is, I do have a steroid cream that is amazing and really clears it up. When I use it my skin, although still red and patchy, is smooth and soft and there's no hard skin to pick. But I'm terrible at remembering to put it on! My family are always telling me to stop. Usually yelling things out like, "Stop picking your nits!" to try to embarrass me into stopping. But of course, it doesn't work. I'll just stop for a while, then go to my room or the bathroom and finish picking in there. I've never felt the urge to eat the skin... but I can't stop picking it. It happens all the time, whatever I'm doing. I do it a lot in bed before I go to sleep and just after I wake up. My bedroom floor is covered in flakes of dry skin and I have to make sure I sweep it in case anyone sees. Sometimes I'll have picked off all I can, and I still can't stop. My skin ends up bleeding and sore, and sometimes just weeps clear fluid. I'm terrified I'll get some kind of disease or infection from it. I really really need to remember to keep putting the cream on, but I'd also like to be able to just stop picking regardless!