Hi, 67 yr old, I'm 65 and I truly understand your frustration, except no spinal surgery, I am so sorry you had to have surgery.
As for CIC, I'm going on 17 years with no answers. I had twins 45 years ago, so I get the pregnancy reference. Fast forward to now, I have to keep my 💩 very fluid up to and including diarrhea. Nothing works. I use miralax to keep me out of trouble. My smooth muscles that are used to push out the poop seem to have completely gone dormant. I have been diagnosed with primary Hyperparathyroidism now. Elevated calcium levels wreak havoc on our smooth muscles and lots of other symptoms too. Look into it, it affects women of our age the most. But I have had secondary Hyperparathyroidism due to celiac disease for 17 years. I am having surgery to remove 3 1/2 of the 4 glands. I have learned that this surgery needs to be performed by only a super specialist who does hundreds of these surgeries a year. Good luck, who knew that we would ever have to feel the yucky part of pregnancy again at our age.