She is up every 1-2 hours raiding the fridge. She only weighs 114 lbs. She can't be hungry. Could something in her brain be making her think she is hungry. I'm not exaggerating when I say 1-2 hrs. Even we hear her banging around. I dont care about the food, but she poops constantly and that is another story. This demensia attitude has just really come in to play Fter they put her on pain meda.
There are two things to consider with this behavior - primarily is it likely to affect her health and the secondary factor being is it sustainable from a financial point of view?
From a health perspective, you should seek medical advice. However, I'd guess that she is metabolizing the food at a very fast rate thus she is not putting on much weight. The type of food is important too because high sugar, for example, may give problems whereas high-fibre may well be passed through. A medical view is critical here.
If the medical advice is that the eating is not a problem (and if it is not a financial issue) then they may be able to suggest appropriate 'snack' foods which might - or might not - be fibre-based.
But if the eating needs to be managed, then you may need to find ways to do this. With my father-in-law, we take his meals in to him and restrict his access to snack foods. This limits what he can get. We do not, for example, leave him with bread - only butter. When it is time for lunch (eg.) we take over some bread. This is often handled with 'yes, you've run out of bread, we'll have to buy you some but here's some of ours in the meantime'. It works, time and time again.
In some cases, snacking is actually a symptom of a different problem. She might simply be bored - distracting her might work well but providing her with engaging activities in-home or at special activity groups may focus her on other pursuits. Eating, for all of us, is often just lower-order-need satisfaction and a symptom of boredom, anxiety, frustration etc.