I have very similar problems. I was having severe lower abdominal pain in one spot--so did colonoscopy--and when finished they told me I needed immediate surgery my intestines had shrunk to the size of little finger. Had a colostomy--which they said they would reverse in 6 months when it had had time to heal. Only the second surgery my intestines kept ripping apart when they tried to put me back together. Upshot I had 4 surgeries over 2 years, got sepsis, almost died, got through 3 colostomies and one ileostomy--all of which leaked constantly--ugggh. But eventually they put me back together. Year since then I had spontaneous rectal bleeding then the MOST painful episode when they told me I had torsion from all the scar tissue. Told me had to go on FODMAP diet--which is insane. No fruits, no vegetables, no dairy, no caffeine, no whole grains.
Basically I can have meat and white rice, white potatoes, sourdough bread. All of which I had eliminated from my diet years ago. (Not all meat--still ate chicken) I've been trying adding a few things back--I do okay with bananas & avocado, kefir, and one or two spoonfuls of steamed celery or onion. Trying yams next.
But I still have a pain from time to time in that origianl spot where they cut out my gut--don't know if it is like phantom limb pain or what.
Seems like the FODMAP is basically just "let's cover all the bases in case". Someone somewhere must be doing research on a beter approach?