sorry to hear of your problems, but quite a few questions are a bit evasive, what age bracket are you in? do you go to school where you are? did you have to move because of your moms work?
why not try talking to your brother and maybe life in his household isnt all its cracked up to be (grass is always greener etc?)
Finally i think you need to find out if your mom is planning on living where you are full time, in which case you have to either start trying to get to know people your age in the area, or let her know that your not happy, and see if there is any chance you can go back to where you were before (if that was better?) Cant be easy for your mom either if she and her b/f have split up, maybe she is unaware of how unhappy you really are? Could you suggest staying with your brother and dad just to see how much better you might 'think' it is, sometimes life is not always what it seems?
i know it hasnt been great advice and i really feel for you, especially at this time of year when everything is MEANT to be happy happy happy, but if its any consolation....... it rarely is!! Glad when its all over?? me too xxx
Take care