Welcome to the forum. Thanks for your question.
Most important for your peace of mind, your negative HIV test is virtually 100% reliable. Even with the highest possible risk of HIV (say you had injected HIV infected blood into your veins), the test result rules: it shows you were not infected.
On top of that, the risk from the exposure described was zero for all practical purposes. It is true that HSV-2 increases the risk of HIV if exposed, but first you have to be exposed, and almost certainly you were not. Statistically, there is under 1 chance in a thousand your massage partner has HIV; and even if she did, the virus is rarely if ever transmitted by oral sex and never by hand-genital contact. And even if somehow you came into contact with HIV, the increased risk in people with HSV-2 is only doubled. "Double" sounds like a lot until you think about it: if your risk of getting HIV was 1 in 10 million, with HSV-2 it rises to 1 in 5 million.
Finally, you don't necessarily have HSV-2. I agree the chance is pretty good -- assuming your wife's diagnosis is correct, and that you have no symptoms of it, there's probably around a 50:50 chance you're infectd as well. You could find out, if you would like to have an HSV blood test someday. But if you're OK living with some uncertainty about it, as apparently you have been doing a long time, there's no special need. It's up to you.
In any case, don't worry about the nonmarital exposure. There was no chance you caught HIV and the blood test confirms it. Even though 3 months is the official time for definitive HIV antibody tests, in fact almost all results are positive by 5-6 weeks and for sure by 6-8 weeks. See
the thread linked below.
http://www.medhelp.org/posts/show/1744700
Best wishes. I hope I have helped ease your concerns-- HHH, MD