Hello @lizzie12 and welcome to the Osteoporosis support group on Mayo Connect. You are asking good questions, and this is a great forum to learn more about the experiences of others. I am providing links to two discussions on these medications. I encourage you to read these discussions and then feel free to "Reply" to any post and ask questions.
--Reclast Infusion
https://connect.mayoclinic.org/discussion/reclast-infusion/
--Prolia and its side effects
https://connect.mayoclinic.org/discussion/prolia-and-its-side-effects/
I am in a similar situation; in that I've had three surgeries of the upper digestive tract and have not been able to tolerate the oral osteoporosis meds without difficult GI symptoms. So, I am also trying to make a decision on the best medication.

Although, you don't mention it, I'm guessing that you have an endocrinologist that is following you (in addition to the Rheumatologist)? You have probably had blood work to determine if you have high parathyroid hormones?

How long ago was your osteoporosis diagnosed? In what area is the bone loss the greatest? Are you involved in any exercise program?

I look forward to hearing from you again.