With morning tummy sensitivity, I'd be worrying about whether she is going too long btwn meals. With some dogs, it can be as simple as giving a little protein treat late at night, right before bed -- have you tried that yet?
You also have to wonder a bit about reflux or IBD/IBS. With reflux, they'll usually swallow hard a few/several times in a period of time - and also they tend to lick their mouths at the same time. If that's indicated, then you can give something like Pepcid. If it's IBD/IBS, then I think I'd want a prescription from the vet for something proven to be effective. Ulcers are another possibility to think about, and those are often managed by a med called Sucralfate.
So sorry your kiddo is having problems - it's terrible to watch them go through tummy issues/not eating - when you don't know how to help them or what's going on. You're taking *such* stellar care of her though - so I know you'll figure this out eventually and get her back on track
. Please keep us posted. Best of luck!