I'd also add that diet alone is not going to help you. Excercising when you have up times is the most important way of handling the stress and the pain. I've found that Yoga on tape (I use AM Yoga, but any would do) helps tremndously, and walking as well. I walk in the morning before I eat, or at lunch before I eat. And of course, drink plenty of fluids.
Breathing techniques are also a good way to bring down the pain level when it's going strong. When you cry, or scream out in pain you are just twisting the muscles tighter. Breathing deeply helps get oxygen and blood to your body and helps the muscles relax. It's painful, but listen to your body and it will tell you what you need to know. Mine lets me know when to avoid certain foods I know will affect me, and it lets me know when I need rest and relaxation. Too often, we get reliant on drugs to help us through, and we ignore how we actually feel. Despite the disease, it's your body.