Not the OP, but my experience with Lyme 25+ years ago in New Jersey was similar. I took oral and IV antibiotics over multiple years. The antibiotics I recall taking are Claforan, Ceftin, Augmentin, Penicillin, Ampicillin, Rocephin, Doxycycline, Azithromycin.

While my symptoms would often improve during/after a course of IV antibiotics, they would always return. I don't ever recall thinking that one of them was what cured me. It was more like the symptoms gradually tapered off over years. I do, however, credit my MD's willingness to aggressively treat the symptoms with my eventual recovery.

Interestingly, both my MD and his wife (also an MD) had Lyme, as did at least one of their children. My advice to people who think they have Lyme is to seek out a physician that has experience in treating Lyme and a willingness to do so. At the time, there was a lot of pressure in the medical community to simply give two weeks of oral doxycycline and then tell the patient that they have to live with whatever remains.