Evenity vs Forteo/Tymlos for first Osteo drug?

Hi everyone,
I am 61 and received my 1st dexi last June despite yers of me asking for one. My dexi was horrible, shocked my doctors. I have severe osteoporosis. I had a feeling it would be bad, but not this bad. ( I have had 2 periods of rapid significant weight loss in the last 10 years, serious ongoing stress, limited ability to exercise due to chronic back injury, and family histroy of osteo yet they wouldn't give me a DEXI till now!) I can pull up the numbers but honestly it makes me so anxious that I try to avoid looking at the report. I am deciding between Evenity or Forteo/Tymlos. The doctor wants me on an anabolic first.Evenity would actually be cheaper for me as it's covered under Medicare Part B while Forteo co-pay is $900/month for me! I am medicare due to disability with my back. I am terrified of having these meds cause more back pain. Also I have chronic muscle and general fatigue and these meds seem to have potential side effects on muscle/bone aches. Also I'm concerned with the Evenity and the potential unintended immune response, since my chronic muscle fatigue is likely of autoimmunity cause (immune mediated reaction to a virus, 40 years ago). The physiatrist doctor in my smallish town doesn't seem to know much-she says they have the same efficacy and rarely have side effects. Well that is not what I've read! I'm scared and confused. Thanks for any guidance.