I don't know what to do

When I was a child I remember throwing sand into my hair just so I can pick it out. As the years passed I moved on to picking the skin around my finger nails. Many years later I still do this but I dont see it as a huge issue. I moved on from both of those to picking my skin. If I have a pimple or an ingrown hair, I HAVE to pick at it. I'll stand infront of the mirror for hours with my tweezers then realize what I've done and get completly disgusted with the way I look. This is gotten so out of hand that my arm, legs and skin are completly full of scabs. The summer is here and no matter how hot it is, theres me, wearing long sleeves and pants. I'm constantly asked "aren't you hot" "why are you wearing a sweater" ince which I reply "I"m always cold" I had always been pretty cautious with my face and really tried to stay away from it..until just recently. A couple people have noticed a few scars here or there and asked about them in which I replied with some lie saying it was a burn. The one person who knows how out of control this is is my husband. I drive him crazy and hes constantly telling me to stop. I asked my family doctor about it not long ago and actually showed him. He looked at me as if I was crazy and said "well just stop picking then" perscribed me with some crazy expensive lotion that is suppose to help clear up scars and walked me to the door. I then needed some testing so while there with the nurse she asks "do you work outside, what are all these scars from". I've had to turn down events that involve being out side for long periods of time, as well as vacatoins. I really don't know what to do anymore. This is becoming way out of hand so I found this site and decided to actually post something with hopes that anyone who has been through something similar may be able to give me some advice. Thanks for listening.