I suggest an endocrinologist. Bisphosphonates render the more potent bone building drugs less effective. Tymlos, Forteo and Evenity would be better ways to address really low scores. Insurance may be an issue unless you "fail" another drug, but these companies have patient assistance programs. I got my Tymlos for free.

Hormone replacement might help in your situation but won't be enough to reverse the loss.

Has your parathyroid been checked?