Sounds like your chronic chafing has not had a chance to fully "heal'. It may look on the surface to the naked eye that your problem area has recovered, and you went back to your fitness routine before it really was cured. Or you never stopped. Something as simple as the chlorine from all your time in the pool could be the culprit that keeps it from fully healing.
Since it seems to be persistent, you might want to get a culture done of that area to see if perhaps it's something other than jock itch and would need different treatment. You might want to see if you can be tested for allergies to certain fibers, like spandex. Meanwhile, can you change out your spandex for something cotton-based? If your chronic problem goes away, voila.
You might want to discuss with your doctor (dermatologist would probably be in order) what product you are using right now to address your chafing. It could also be that it's reducing the symptoms but not eliminating the underlying issue.
Regarding the gold bond powder, I'd switch to Cornstarch-based powder. My chronic chafing/jock itchiness went away about 10 days after I switched. I still do use a jock itch spray a couple of times a week; that seems to help keep my issues in check.
Hope this helps. Keep us posted.