Ugh... I've been putting off seeking any guidance for a long time...

Hey.. I'm a 20 year old married female with loving parents and siblings and a wonderful husband. I am an intelligent sophisticated young woman who is modest, compassion, and confident. I have been diagnosed with Borderline Personality disorder as well as anxiety disorder, when I used to self mutilate with instruments such as razors or pencils or safety pins, I only use my fingerenails now.. I don't feel bad about how I look or hate myself even in the slightest bit but ever since I can remember I've been picking and scratching at my scalp, legs, thighs, fingernails and genitals.. Especially the genitals. When I was a child and my parents found blood in my underwear I told them that I just fell down, I was very ashamed of my compulsive scratching even before I knew it was unhealthy and bad for me. I've always had a healthy perspective of sex and human nature and I really don't understand where this compulsion even came from. I'm ashamed of it, I hate it, I've only ever told my husband about this problem, not a soul knows besides him. He has tried helping me by stopping me when he notices I've been in the bathroom a long time or if he sees me noticing small things that I'll usually go to pick, but I want to have more control. I'm afraid that I'll be like this the rest of my life if I don't figure out what's wrong with me.