I would get her teeth looked at. It very well could be she is having troubles with her molars, if you do rule out her molars, then it could be picky eating, but she should be eating pellets.
I would not offer her veggies, "if" she has shown diarrhea in the past. That could make things worse. Have you tried a slurry with her to see if she will eat? Water/unflavored pedialyte mixed with pellets to soften them. With the excess water/unflavored pedialyte in the slurry I would be once again worried about the diarrhea.
With her weight loss, are you checking weekly or was the last time you weighed a month ago? I would (if you are not already) keep track of her every other day until she gets over this not eating. If she loses more than 4 ounces in a week you should be on "RED ALERT" and have her in the vet that same day.
That is all I can think of now. I will go and see if I can find anything else worth sharing.