Hen Pecked

We have a broody hen.  Her name is Mama and she is the best mother hen.  She has hatched several batches of meat chicks for us.  When a hen goes broody they sit on the nest eating and drinking very little if at all (the nest would get quite messy if they did). Mama goes broody 2-3 times a year and it takes a lot out of her.  She is skin, bones and a mass of feathers.  She has only been broody a week (mistake number one) and the chicks I bought yesterday look about a week old (mistake number two).  Under the cover of darkness last night we tried to sneak them into the nest. She was a bit resistant, pecking at us but we thought she would settle.  This morning she continued to peck at the chicks, driving them out of the nest.  Ugh!  So now I have 8 chicks in a brooder and a hen that I need to break of her broodiness (she's sitting in a dog crate in the backyard, cooling off).  It's so much easier to let the mama hen raise the chicks.  I hate to have to hassle with heat lamps.  But that's where we are.