Hi Surfergirl,
Here is a resource for you...
http://www.selfinjury.com/index.html
The best advice that I can give you is go to this site. And to get some counseling to find out why you are doing what you do.
There is always an underlying issue to this type of behavior.
Please do not beat yourself up over this. You can get help. Keep posting and let us know what is up.
Hugs, Karen