Both webmd.com and medicinet.com have very good explanations of c-diff. I found one change since I last checked it out. It used to be an infection that was transmitted in hospitals and nursing homes. People who have been on antibiotics no longer have the beneficial gut bacteria to prevent c-diff from taking over. And, usually, a crohn's patient has been on immunosuppressives, too.
But both sites say that it is considered an epidemic because it is no longer associated only with in-hospital stays and nursing home patients. It has become resistant to the old treatments, but there are new ones that they say are very effective. I'm sure these new treatments will help you.
Even so, a high quality probiotic, plain organic yogurt, and a diet low in highly processed foods helps almost everyone. It took nine months to eliminate my crohn's diarhea. In any event, getting back to eating real food can't hurt anyone. I wish you the best.