Or just say you're the s in a SM relationship.
People with IBS have food triggers that make them sick. Could be dairy, gluten, grains, alcohol, sugar, whatever. Cut one at the time to try and figure out which ones are causing problems. You said you ate "pizza and juice", doesn't sound like a healthy diet. When you got diagnosed with IBS the doctor should have referred you to a dietitian, you can't just eat random junk food.
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