Should I run away from home? Part 1 Please don't answer on this one until you've read Part 2?

I am 13. My parents are divorced. Both have custody over me but my dad works shifts and so my mum has residency. 

Mum: My mum's side is constantly having family fights which causes me stress and I'm always asked what side I'm on and I don't know what to say, and if I say something she disagrees with I get in trouble. For stating my opinion. She is overcontrolling and dictates what I wear and what I do. She favours my younger sister. She doesn't let me say what I want and therefore I lack in self-worth and confidence. I don't know how to talk about my feelings to others aswell; even typing this is taking really long due to me thinking about what I'm trying to say and how to say it. I've been here for 20 minutes. She tells me to be more grown up, but when I do I am being 'aresy' and a 'cow'. I can never do anything right and am not respected. I have no privacy; she always looks through my phone and if I ring someone she wants to know who it is and why and I get in trouble no matter who it is, and she always just barges into my room. I'm always put down about what I like and the way I am. My step-dad is like this too. On the other hand, this side of my family is quite well off money-wise and have a fairly big house. I have a pet, nice clothes, decent food, warmth, and all things like an ipod, laptop, kindle, etc. In short, I am brought up in a cold lonely and shunning environment but with a good lifestyle. But I'm very unhappy here.