Okay, first of all SSRI's are usually very helpful for IBS. Even a low dose of an SSRI can calm your gut.

Please read everything you can find online & even check out some books about IBS. It is a very real, extremely disabling, and surprisingly common condition that just takes some figuring out to discover what works for you. IBS and anxiety disorder often go hand-in-hand. So much so that medical science has come to the conclusion that the two disorders are interrelated.

There's tons of info online...Here's a start... Is there a relationship between psychological symptoms and IBS? - aboutIBS.org and What is the relationship of stress to IBS? - aboutIBS.org