I just posted on another similar thread and directed the person to the thread on the next page called "Bowel/rectal spasms for years" and a little on the "constant diarrhea" thread on this page.
As I mentioned before, I've tried numerous elimination diet with no success. But the gastro doc said my issue is about
motility. Evidently, things don't go through as they should; the bowel doesn't function correctly.
Perhaps some of the things I do (mentioned on those threads) may help you, too.
Best wishes and I hope you're better soon.