The general medical consensus is that "chronic Lyme disease" doesn't exist and that symptoms attributed it often have to do with chronic fatigue syndrome or infection-triggered fibromyalgia.
Doctors generally believe in fibromyalgia. What's more controversial is whether it's a disease, disorder, symptom or syndrome.
A patient experiencing fibromyalgia is very obviously unwell, but in many (not all!) cases it's comorbid with depression and treatment with antidepressants and therapy helps with both the depression and fibromyalgia.
As of right now, it's not especially clear what things like fibro and CFS are, and whether they might be mental disorders in some cases, but they're definitely real.