I have read your posts and I'm sorry you are having so much trouble. You have gotten a lot of great advice from some of the others.
I am one of the few that cannot tolerate SFS. There are a couple of gals on the boards that can't either. It made them feel so crampy & gave them explosive "D". I do better without it. I know it has helped so many on the boards but I just wanted you to know this as another approach for help.
I do better when I eat things like pasta, breads, rice, baked or grilled chicken and stuff like that. I can eat some veggies if they are cooked....like carrots....but certainly not cucumbers. I get my fiber from oatmeal.
I also take Librax. I started taking it 3 times a day 30 mintues before meals. It really helped me. I am down to 2 tablets a day now and sometimes on a good day only one. Imodium has been a must for me and also Phazyme for gas.
Also, I noticed you mentioned a food diary. That is one of the most important things you can do. It helped me immensely.
Be sure and check for Sorbitol in anything you eat or drink...even chewing gum or candies. It gives my tummy a fit.
I hope you feel better soon and that some of these ideas will help you.