L.,
Okay, as a female I went through this right after I got my period. I had friends who's Mom's didn't 'pay attention' to what their kids were doing, and let them use their allowance for whatever they wanted. My Mom was, however very much an active part of my life.
At any rate, I rebeled and wanted to buy cheap lipstick and eyeliner and even resorted to hiding it from my Mom. That lasted all of two week, my Mom was a teacher and she found out pretty quickly. At the time, I felt like my Mom didn't understand me...she was the only person who was against me...blah, blah, blah. My Mom had her sisters (my aunts) talk to me, and ask if they could take me shopping and show me how they did their make-up. It was a great day, and I felt like someone got me. My aunts and I have always been close, and this was a great outlet for me...I had 'other' females who I could talk to about things I didn't feel my Mom would hear.
Truly, it is a phase. My Mom and I are best friends today and have been super close always, but this phase I think can either make or break a Mom/Daughter relationship. If you push her and deny her things, she will most certainly rebel and fight back. If you find ways to comprimise, and make this an experience she can look at as positive then you'll come out on top.
Does she have an aunt, sister-in-law, brother's friend, cousin...someone older who can offer to help her with her make-up, clothes and things like that. Sometimes an outside female can help your daughter see the light easier than it coming from Mom. My aunts helped me to see how I was treating my Mom wasn't fair, she like you, worked hard and did whatever it took to make our family successful.
If you don't have an alternate female then, my suggestion is sit down with her...talk to her, don't demand, yell or be mad. Explain that you understand she's growing up, and that there are things she'd like to try and you'd like to be a part of that too. Tell her you'd like to take her shopping, so you can both learn about make-up and get some things that are appropriate for school. Take her to some place like the Body Shop or Bath and Body Works...some place that offers make-up but, has subtle shades that are more age appropriate. You could go to the mall too, and have one of the make-up artists explain how make-up effects the pores, and what is right for her age.
It could be a learning experience for both of you...and who knows...FUN.
Her attitude overtime will change, as she moves into her next hormone driven phase. Think about how you deal with your toddler, the patience and understanding you have had to have with her phases...my Mom (high school teacher) calls it the terrible teens.
I would make sure she understand that her brother abides by your house rules, and that she is no different and will be treated with the same discipline as him if she continues to be rude and treat the family poorly.
But, really I just remember feeling lost and alone at that age. Your hormones are all our of whack and you've got pre-teen girls telling you how awful their Moms are...so, it's easier to make your family out to be evil too.
I wish you the best of luck during this time!
D.