12 year old horrid behaviour - pre diagnosis Aspergers

I really don’t like to be writing this as it’s such a negative post but I am struggling with my daughters unkind behaviour. 

 We are pretty sure our 12 year old daughter has Aspergers.  She is growing up and I completely understand that she will have hormones fizzing about and she does struggle socially.  We want to do all we can to help her but her nasty behaviour is grinding the family down and causing upset every time we are all together. I am at a loss as to how I should deal with the issues if they are sensory issues or plain horrid. 

For example she calls people names and is negative about people’s appearances, if I have my gym kit on I am glared at and told I need to get changed, if my hair is back in a ponytail I am told I am dirty and should wash my hair; I am told I must wash my hands before I do her hair for her, I am not to touch her food as I am dirty, she also mimicks my voice and the things I say.  She’s like an echo,  I have found myself being more pronounced in my speaking voice and cross checking my own clothes,  I am also starting to become anxious about this and I also don’t feel there is anything I can do to “punish” her.  If I take her phone from her and say she can have it back when she can be more polite but she doesn’t care about any material possessions, and she is not scared of me as I would have been of my mother.  She seems to enjoy seeing me cross and hurt and she is really pushing every button.  

I do consider myself a caring kind parent but I am struggling with finding a strategy to get through these insults and to work out if it’s part of her sensory issues.  I don’t want to feel negative about her. 

Hope someone can offer some advice, please :)