Erica, I have struggled with this all my life and have tried just about every food, fiber supplement, and medication available.  I finally have found a system that works for me.  

1)  I stopped drinking water with my meals.  Instead I drink wine, tea, or nothing at all.  I can now digest my food better.  Perhaps the water was diluting the gastric juices, digestive enzymes...I don't know. 

2)  I increased my fiber.  The easiest and most enjoyable way for me to do this is flax meal.  Not flax "seeds," but flax MEAL.  It is ground up seed.  I add one or two tablespoons to my yogurt every morning.  You can also add it to a lettuce salad or fruit salad.  It actually is quite tasty.  It reminds me of cookie crumbs.  Look for an organic version like Bob's Red Mill.  It's my favorite brand of all that I have tried.  Your local co-op will also sell it in bulk.  It must be kept in the refrigerator or it will go rancid.