Have you had all the tests to diagnose IBS? Have you had a colonoscopy, endoscopy, blood work, etc.?
Are you C, D, or A?
I am sooooo sorry to hear you suffering so much! As a kid the pain and gas would get so bad I would throw up from the pain! my mom thought I was bulemic (I was anorexic but I would NOT make myself throw up!) That was the only thing that would make the pain better (temporarily).
The best advice I can give: Get everything ruled out. Get regular sleep and exercise. Drink loads of water. Find things that relax you. Consider the hypnotherapy audio option. And keep venting. We all understand your pain (unfortunately)