Is there anything I can do?

I've never heard of a site/blog like this but I'm so glad it exists. I'm relieved I'm not the only one out there with this kind of problem. I don't know what to do anymore, I've completely destroyed my body. I've seriously had moments where I've burst out in tears because I can't stop or make it go away. I've dealt with it for a while now but just recently it has gotten worse. I only pick on my arms and legs, but they are repulsive! I tell my self everyday I will stop, somehow condition myself to not do it anymore but it's IMPOSSIBLE. I even went and purchased $40 dollars worth of scar/scabbing lotions and cremes but of course none of them are doing anything because I won't let the scars heal. It's actually beginning to make me REALLY depressed. Summer is coming up and I don't know how I'm going to reveal my skin/body. I'm 21 years old & attend college, I know my classmates will be disgusted and shocked by my arms. I can't even go out to clubs/bars without having to worry about my arms and legs. My friends and family don't understand why I can't JUST stop, and quite honestly I don't know either. I really feel like something is wrong with me and I'm tired of it taking over my body. I mean, I've always had self-esteem issues but for the most part, I've been reinforced from society that I'm a pretty attractive girl ...when I'm covered up. My scars/scabs are hideous and they're making me feel even more hideous. I don't know what do to anymore, this is sickening. I've always thought about seeing a therapist but never pursued it. I went to my physician and she merely told me to keep them moisturized. I don't want to KEEP doing it, I want to STOP. So, I don't know, should I make an appointment to see a therapist? Will it work? Are there any specific cremes or lotions that will make this go away? SOMEONE PLEASE HELP.