I am so sorry you are experiencing all of those symptoms! Sounds frustrating, and confusing!
Perhaps, get a new doctor, get a skin culture from your genital area. Also, if it is not Herpes or some other STI, it might be Strep! Anal Strep can last forever and on the off chance she was getting sick when you two had sex, it is a possibility.
Another idea is to look at your diet. I know it might not make sense, but you could be allergic to something that is further exacerbating whatever is going on. Remove sugar, refined foods and especially gluten and see if there is an improvement in the mean time. Also, tight clothing NEVER helps, so hang around the house in some boxers...nothing tight. Let things air out.
I am very sorry. I hope you figure it out. Again, get tested for strep in your genital area.