contamination fears

I have OCD--mostly contamination fears, which I handle by washing obsessively and avoiding touching things. I am afraid, primarily, of STDs, particularly contracting and interacting with oral and genital herpes. I don't even know what the first steps are in getting over this. I've tried Cognitive Behavioral Therapy, talk therapy, hypnotism and medication (very briefly when I was still in high school). The only things that sort of seem to help are exercise and meditation and sleep, and smoking pot. What are some steps I can start taking to address this stuff?