The reflex test is some kind of supplemental test that is supposed to confirm a low positive hsv2 test. Unfortunately, it's not all that reliable, and I'd recommend another WB test.
There are some people who continue to get low positives on the hsv2 IgG test. There's a blood protein that seems to be a cause for it - a totally normal protein, and it seems to happen more often in 1st generation Americans - if that applies to you.
https://westoverheights.com/forum/question/is-there-hope-for-me/
If your last exposure to someone other than your husband was 9 years ago, and you had the negative WB at least 12 weeks after that encounter, you did not get herpes from that encounter.
Your symptoms do not sound like an STD. Have you seen a urologist? I'd wonder about chronic pelvic pain syndrome, which is non-bacterial prostatitis. I'm sure they've done urine testing - have they found any white blood cells in your urine? Were the activities protected? Has your husband had any symptoms? I'd imagine if you had an STD, he'd probably have one, though I don't know what activities you engage in.
I'd also wonder if you've had any imaging of your back. Any of your groin area? Anal/rectum area? A friend had similar pain for a long time and it turned out he had anal fissures, found during a colonoscopy, I believe (it's been a long time). He already had herpes, and was convinced his herpes was causing his pain.
The only STD you may not have been tested for is mycoplasma genitalium. Ask your urologist about it. I doubt it's causing your symptoms, and your husband would likely have it, too, but you can at least rule it out.