Thanks Sarita and Normal.
It does help to hear from someone with similar experiences. It really sucks when a doctor throws up his hands / shoulder shrugs and tells you to "live with it" and get back to work. I'd like to see the Doc try to make it through several hours of surgery with this kind of problem. I assume they feel stress like normal people?
I think the most humbling aspect of this is the "mental" component of "this". I've always considered myself to be very stable / strong, but reading that the traditional thought about IBS is that it's largely about the mind - gut connection, causes a lot of self doubt and more anxiety. I'll admit that stress does seem to make my symptoms worse, but I'm absolutely certain that something physical is wrong. I have problems even when there is no stress at all. I couldn't find any local specialist to try bio-feedback techniques (something I would have considered quackery years ago), but I did try a counselor who started me on stress relief audio and techniques.
I'm currently on a no-gluten, dairy-free diet which is just a ton of fun! My job requires me to be on the road for 4 days at a stretch, so I live on rice cereal, rice crackers, and boiled eggs. I don't dare eat anything at any restaurant - even a piece of grilled chicken is usually spiced up with something that doesn't agree. On the plus side - I'm back to my high school weight, and running is a lot easier.
Thanks again, I hope you all find help and relief.