First, I'm sorry you're in pain and that you have to postpone surgery and deal with the Medicaid application. Pain in the butt. =(
I just had my gallbladder removed a week ago but before that was in pain that just wouldn't end unless I could sleep on it. Woke up with it, went to sleep with it. Bad. Sounds like yours is more meal-related, at least for now. Here is what helped me pre-surgery:
Cut down on dairy.
Cut down on caffeine if you can't remove it entirely.
Avoid high fat food and eat low fat alternatives, like lowfat cottage cheese and lowfat or lite cheese. Avoid butter on toast -- have jam instead.
Avoid chocolate. Yeah, I know, but it has to go.
Avoid red meat and eat only lean chicken and turkey, eat fish.
Eat lots of green leafy veggies like spinach and kale. Avoid eating gas-producing foods like pinto beans, cauliflower, cabbage, and brussels sprouts.
Avoid garlic and onions. They often trigger attacks.
Eat more beets -- not the pickled kind, but plain old roasted or cooked beets. Beets are good for cleansing the liver and gallbladder.
Organic apple juice is good, too.
Eat several small meals a day instead of 3 big ones. Graze. Snack.
Finish your last meal of the day/dinner 3-4 hours before going to bed. Do not eat even the smallest thing after that.
Take a hot shower then a bath when in pain. It helped me a little, at least for a little while, and after surgery you can't soak in the tub for a while so do it while you can.
I also found that sleeping with the head of the bed elevated about 4-5" and sleeping w/ 3 pillows and mostly sitting up helped, but then I got acid reflux that was made worse by the gallbladder. Have you been checked out for reflux and gastritis? They can be made worse by gallstone problems and vice-versa.
Sometimes what helped was sometimes just taking a break and having chicken broth and apple juice for a day then slowly adding solid food back.
I didn't take pain meds for the most part either. Some people recommend acupuncture, but I'd try that and totally avoid herbs and liver/gallbladder flushes because they could launch that stone into your common bile duct, cause LOTS of SEVERE pain, lead to rupture and infection and require emergency surgery. You don't want to do that. =/
Hope this helps at least somewhat.
I hope you feel better soon!