It's a book about a little girl.
I think her mother dies while the father is away at war and her family puts her in boarding school for girls(or she is in the boarding school when her mother dies and father goes missing in war).
So she is made to work their as a scullery maid of some sort cleaning fire grates etc, while all the other rich girls have classes and fun.She has to live in the attic and the woman who runs the place is mean to her,but she has one girl who is good to her.

This little girl lives a lot in her imagination a lot as she imagines herself a princess/queen and she is very self controlled.She sometimes has to go to bed without food and has to walk in the snow to buy things for the home and has a very tortured hard life.

Then an old gentleman moves across her attic and he has an Indian man as his assistant/servant who keeps a monkey(I think).
Then this monkey one day goes into this girls room in the attic and the gentleman find out about her condition but she does not know he knows.So this old man send his servant across every night or day when she is not around to make the room comfortable and place food in the room.

In the end her father returns from war and it is a happy ending and the old man turns out to be a friend of her fathers(I think).

One of the names that I remember from the book is Becky (I think that's the girl who is friendly with the main character).

Does anyone know this book I am talking about?

Thanks in advance:)

Little Princess. It is also a shirley Temple Movie

Yes I think that's the one.
Thank you so much.

It's by Frances Burnett. :)