How do I deal with my out of control 14 year old son?

Hi, I have a 14 year old son who is showing utter disrespect to me & I need some advice on this issue. Me and his dad divorced 3 years ago and since then he constantly blames me for his life. He calls me all the bad names on the planet, trashes the house in anger, swears at me and blatantly says that he hates the sight of me and that I am the worst mother on this planet! I live with my new partner (my son does not like him at all and insults him from time to time again although I must say that my new partner tried to bond with him but failed since I think he lacks the patience and tact to deal with teenage children). Now recently my son's father has moved into my area (this is where my son's school is) and he has decided to live with his father. I feel lonely and devastated due to the constant hurls of insults and demeaning remarks that I have ruined my son's life. A few days after he moved in with his father, the father went on to a holiday with his girlfriend leaving the house keys with a 14 year old child! When confronted by phone he said " Well, you look after the child for two weeks and he will occasionally come to my house for relaxation after school". Now since he has left for the holiday, every evening my son throws tantrums that how much he loves the father's house and that I can't even provide him a decent living etc etc. I am struggling every day to establish a decorum in this house. He doesn't talk but is constantly angry with me accusing me of spoiling his entire childhood by having constant fights with his father ( this is true, while he was growing up me and father had a turbulent relationship and for that reason we divorced) I explained to him that regardless of that my love for him has never changed and that we still are his parents and care about him! He doesn't blame the father for anything. I am one who cares about his studies, worries when he is not home in time and show all the love I have for him whereas the dad is too busy working but earns a very good living and therefore provides all the materialistic aspects to my son. I feel that I have lost my child and it really hurts to see him going so far from me, emotionally. His father is coming back next Tuesday and thereafter my son says that he will never come and see me ever again and that I shall always remain the big loser in my life. My partner is not interfering since it makes matters worst with my son. What do I do? He doesn't want to seek counsel ling. Should I just let him go to his father ( he actually has moved his playstation etc to his house anyway) but I know that the dad and his girlfriend will not give him the love I have for him. Maybe they will discipline him more. I feel devastated. Thank you for reading this and any advice would be appreciated.