Why has my dad changed so much.. I don't think he loves me anymore?

well since i was little my dad was my best friend, my mom had an alcohol problem which eventually led to their divorce. I lived with him and still do...we used to do everything together, hed play softball with me, or wed watch a movie or just anything i could really tell he had unconditional love for me. But then he met my step mom. Me and her never got along, shed try to correct me with everything. They have been together for 4 yrs now. all me and my dad do is fight now.. we'll make up and then we will fight again the next day. He doesn't understand how much he hurts me.. he put his wife before me, or so it seems even though he says he doesn't. Things that used to never bother him, make him want to kill me now(not rly but you get it) Like for example... i went on a little trip with him and his wife, and he let me hook up my ipod to play in his truck because the earphone makes my ears hurt sometimes, and his wife very rudely told me to listen to it by myself. He didn't say anything about it... he just agreed with her, and when i asked him why he did that, he told me not to mention her name again and it has caused a two day fight now... he gets so offended if i say anything about her and he has never once taken my side regardless of whether of right or wrong. he tells me to go live with my mom (which really makes me upset because of everything i went through with her being an alcoholic and stuff) and he told me he cant live another year without me and would send me to a boarding school. I don't know what to do anymore. his wife causes every argument and he doesn't get it. he has no idea how bad he hurts me. i have tried to talk to him so many times, and it always ends in a fight because he cannot stand to hear anything negative about his wife. im laying in my room right now crying i don't know what to do anymore and i feel like there no where else to go.