All the things that you described as possibilities are truly possibilities. You could have had this for 30 years or she could have had it for 30 years and just affected you or she infected you years ago and you didn’t notice oh it’s possible she is not infected. I think it would be wise at this point to have her get an IgG antibody test. So you have a genital lesion that your doctor swab tested, is that correct?
It is entirely possible that a person can be infected for many many years and not infect their partner. I have seen it over and over and I will say that the question of infidelity frequently comes up and I repeatedly say that infidelity is not necessary for this to occur. She is welcome to read what I have to say about this. And if she is still unconvinced, I would be happy to do a video conference with both of you.