Try some gripe water or infacol as she may have colic which normally wears off at some point around 6 months,we've all been there and felt useless and tired and depressed because you cant help,my daughter and son where both like this but it doesnt go on forever,if it still persists i would say take her to the doctors,it may be her milk or griping pains in the stomach where she is getting used to food in her stomach,sorry im not much help but i dont think there is much you can do if all is well with baby! : )