Keep her at it -- What she is going through is normal!

The radiation definitely will change taste because it is cooking the taste buds -- Metallic is one of them -- It's a bit different for each of us, both the initial effects and the recovery effects.

At first the only taste that came back was salt, in fact one of the first things I tried to eat was out with friends and a cup of veggie soup; tasted to me like someone had dumped a whole salt shaker in it! Had the others take a taste and they said it was fine -- Prior to my most recent surgeries, after two years I still wasn't really tasting sweets and taste was basically fading after a just a few bites.