I have heard that soluable fiber supplements will help with the mushyness to your stools. It should help to make them much firmer and more formed. Try citrucel or metamucil.
Yogurt might help. It stimulates the immune system, crowds the bad microflora by helping the good bacteria grow in the intestines. (The probiotics in yogurt are also good for those taking antibiotics that cause them to get diarrhea.) -Just a thought.
MYST
-Oh yeah, and you'll want to make sure the yogurt has 'live active cultures' in it. It'll be on the label. And whey protein too.