Please don't despair! I can tell you there is hope. I had major major bowel problems myself and it took me about 15 years before I finally learned how to help myself.
I did the traditional medicine path and saw doctors upon doctors including 2 specialists at Stanford Medical. They did nothing. Worse than nothing - they took away my hope. I had gastroentiritis, and was always getting food poisoning or diarreah or was constipated and also had one of my nerves being pressed on by my colon leading to excruciating pain. I also got a major case of dysentery (didn't know people could still get that) from Antibiotics I was given.
Here's what worked for me: First, I think being vegetarian helped, but I needed something that would be really powerful and strong. I found about Dr. Schulze 's formulae (his info is here on the curzone site). Primarily, I did his intestinal formula #1 and #2. This has made all the difference. The #1 completely helped my entire intestinal system and my intense pain has gone. The #2 got rid of many toxins as well and my intestinal flora are in balance now. He also has the Superfood which gives excellent nutrition and has helped balance out my intestinal system as well. This has worked for me and my symptoms are *all* gone and I feel better than I ever have, but it has been a long and painful road.
This has all come about fairly recently for me, and I am also starting to explore the "water cure" mentioned on this site and I plan to do a liver cleanse.
I can only talk about what's worked for me but I wanted to respond because I know how it feels to feel like your life is over and no one can help you. Obviously you are ready to take your health into your own hands, and this is an amazing blessing. Keep learning and best of luck. This is my first time posting and I wanted to because your situation really hit home for me.