*always* consult your doctor (or several of them) before trying anything!
I've had Fibromyalgia and accompanying IBS my entire life (26+ years). my personal description, which my doc said was the best analogy he's heard yet for such stomach turmoil is "like unseen hands wringing out your intestines like a wet towel". i've had countless months-long cycles of 10-25+ very loose bowel movements per day. it's *awful* and can literally throw your quality of life down the toilet and lead to nasty depression and social withdrawal, though you can take pride in knowing you're keeping TP manufacturers in business
while nothing i've discovered works 100% of the time, i agree that the *best* way to break the cycle of stomach trouble/rapid-fire bowel movements, cramping, burning, bloating and the like is indeed *deep, slow, relaxing breathing* for at least 10 minutes or more a day. if your stomach is all knotted up and "tight" or tense (causing nausea, loss of appetite, the "runs", etc.) deep breathing, preferably with meditation, prayer, or other relaxing/positive thoughts are your best bet to break even the meanest months-long-"when-will-it-ever-end" stomach trouble. watching funny movies, TV, or humorous/light-hearted literature can also help tremendously.
the deep "pit of your stomach" breathing may actually *hurt* for a while at first if your gut is tense and knotted-up, but force yourself to continue for at least 10 minutes and the discomfort will often fade away almost miraculously!
trust me, i've tried everything, and this is the best route to take. problem is, it is quite easy to slip back into "stress-mode" and end up back at square 1.
after going to tons of doctors and undergoing countless tests, the only two prescriptions that help me personally "put the brakes" on hyper-bowel movements are Lomotil
in combination, as prescribed by my physician(s). Lomotil is an old and common anti-diarrheal Rx, and Welchol, while typically used to treat high cholesterol, helps form the stool withouth interfereing or interacting with anything else in your body (and after you've had 20+ loose moves in a day, a formed-stool is like heaven
also, as others have said, avoid any known or suspected triggers like spicey foods, too much caffeine, alcoholic drinks (like throwing gas on a fire), carbonated drinks, and even dairy if you may have a lactose-intolerance issue. again, always
consult your doctor, and bug them to death if they don't take you seriously, and NEVER be afraid to get a 2nd, 3rd, 4th or even 5th opinion when it comes to something as serious as this. GI problems can be very serious health/nutritional threats. get as many tests done as you can to either identify or rule out possible conditions.
hope this helps somebody out there, even though the original post is over a year old!