Do you take a fibre like Metamucil for your IBS? It absorbs the water in the colon and it bulks up the stool so its easier to pass. I take it every night before bed, its something that should always be taken if you have IBS. Don't take the sugarfree one the aspartame is not good for IBS.
Do you take any PROBIOTICS? They are very important to replace the good bacteria in the colon try to find one with at least 50 billion live bacteria in the refridgerator at a health food store. Take them morning and night on a empty stomach they really help with the diarhea. Watch what you eat if the foods you say bother you cut them out completely. Exercise is a great because it calms the mind and the gut. One medication that I use so I am not panicking about washrooms when I go somewhere is LOMOTIL I take 1 after my morning BM"S and I'm great for the rest of the day. You need a perscription for it, but it is a lifesaver.