Your girlfriend should break the sleeping habbit slowly, after the child is alseep, move her to her own bed. Then when it's nap time, lay her down in her own bed so she is used to falling asleep there. I think it would be the quickest way. As to giving into the candy and cookies all the time, it is not healthy for the child. She needs to eat healthier snacks, like sliced apples or maybe oragnes. Something sweet but also good for you. As to the crying when her mom leaves, her mom needs to stay gone, she will settle down. Or distract her when your girlfriend leaves, she won't notice she has left and then when she come back the child shouldn't be crying. Good luck.