Some LLMD's spend too much time chasing lyme and many of the other issues are ignored. I'm a firm believer that these other infections are the main cause for lack of energy and muscle fatigue upon slight exertion etc. Sometimes it is a waste of time and $ to take test upon test to figure out what infection you have.
Many in the lyme world find better results when they start to try different med combos that target different organisms besides bacteria. I spent 2 years chasing lyme with amoxicillin, doxycycline and omnicef. I only received about a 50% decrease in symptoms. Then i started to explore different meds, Biaxin, Roxithromycin, Bactrim, Artmenisin, Rifampin, Minocycline, mepron, malarone etc. These were the meds that brought me near 100% of my former self. I think there are unknown protozoal infections, viruses, Bartonella, Babesia etc that are commonly missed.
Heck, some even have good results with antiparasitic meds such as ivermectin or alinia. Or antivirals such as acyclovir, valcyclovir, oregano oil, olive leaf etc.
Moral of my post, there is more going on then just lyme. Eventually you will find a nice combination with broad coverage that will bring you to the finish line.