Bori had you noticed anything off with the frog's health? Has their been any diarrhea, vomitting, redness of the toes and stomach, bloating, dry skin causing bad sheds, etc? Any of these signs mean your frog needs to go to a Vet and get checked out. Meds will need to be prescribed.

Also your frog stopped eating before winter set in correct? This is sometimes normal and I say sometimes because if any of the above symptoms are present then it isn't normal. In the winter months they slow down. If you are having difficulty maintaing the temp levels that will keep the frog from returning to its fiesty self. Now when they are in their winter slump there isn't a whole lot you can do to reverse their natural instincts and the frog is able to sense seasonal changes. It is getting close to their breeding season so hopefully your frog will snap out of it soon.

Have you tried pinky mice?