I also had a Colonoscopy, Endoscopy and a Barium Meal last year after all the SIBO symptoms started showing up and of course they did not show up anything of substance to tie it to my symptoms. So that is why my GI Dr concluded that it must be SIBO and treats it as such. When the antibiotic treatments I take from time to time work for a short a time, he is assured that it truly is SIBO. I am trying the natural route but I have yet to find one that truly works. So I just continue on! As you say "I am stuck with this for life"! So we keep reading, testing and trying!!!