It is very very common for lesbians to be "boy mad" at a young age. It is a way of trying to deny the reality. Like forcing themselves to like boys. She may or may not be a lesbian, but being "boy mad" a year ago does not tell you which it is.
Often as mothers, we can have ideas about how our future relationship with our kids will be. So you can dream about shopping and sharing make up tips with a girl. But of course children do not always grow up to be how we imagine them to be.
Given she is not interested in how she looks, taking her shopping and to the hairdresser may be seen by her as a criticism, not an attempt at bonding.
I think the best advice I have ever heard about parenting is to parent the child you actually have, not the one you want. It sounds as if you are parenting the girl you want.
And it is very common for parents to visibly favour one or more children over others, but not see it. I have seen it many times. It is hard to see a situation as it really is when you are in the middle of it. If she is saying you favour her brothers, then she certainly believes that.
Favouring is not about who you spend most time on. It is about positive interactions, how harshly you judge someone, and how much you show you care. When you have a negative relationship with a child, you can get into a spiral that is hard to get out of. Most of your interactions end up being negative ones, and this just reinforces the poor relationship. Read How to Talk so Kids Will Listen. Actually listening to teenagers can make a big difference to your relationship. Most parents think they listen, but they don't.
So if she says - I am unhappy with xxxx. Most parents jump in and say you are wrong to be unhappy with that, or that is not what happened. That is not really listening. It is hard emotionally, but just listen to what she say. You can say things to show you are listening like - you sound very angry, or you sound very hurt. But by listening you will get a better idea of what she really thinks.
Every day she caused arguments between everyone
Sorry but this is not true. It takes two people to cause an argument. She may start things, but it is also about how others react.