Do TCAs or pregabalin actually resolve the cause of the muscle pain, or do they effectively function as painkillers?

Been dealing with fibro symptoms since I was 12 and it's gotten to a point where literally every muscle, no matter how small or trivial of a band, hurts and has trigger points/adhesions all along the fiber. I've had neurologists and rheumatologists suggest going on a TCA like amitriptyline or nortriptyline, or Lyrica/pregabalin to help with the pain, but I'm really resistant to the idea of going on a medication that won't fix the root cause. I'm aware that the longer you're in pain, the more sensitive you become to it due to central sensitization, and the medications hypothetically help kill the pain signal feedback loop. But after tons of research (medical studies, trials...etc.), it doesn't seem like rewiring your CNS to reduce pain signals is what will "fix" the underlying cause of your fibromyalgia once you stop taking the medications.

Has anyone found that going on these medications and then going off them has led to lasting effects on their fibromyalgia symptoms? How is it any different than just taking painkillers (assuming they're equally effective for you)?

I don't know if it's quixotic, but I really WANT to be a functional, pain-free person without requiring long-term dependency on medication (or hopefully going on medication at all).