Mum is a little angry with herself

Well as you know I have been on my diet as per the vets instructions, so I went from 132grams in april, and I finally lost 16 grams and got down to 117 grams, mum was over the moon happy as larry... until today when she looked at the scales and I have gone up to 123 grams, she is beating herself up about it, she knows it is her fault for feeding me too much, so she is a little angry with herself today, so back on the diet for me I think. this is going to be hard as Xmas is coming up and she is going to be home with me for 12 days solid. ooooohhhhh this is going to be hard. IT MUST BE DONE....