Judge Morris said Rees then, "in a bullying cowardly way", had grabbed the victim by the hair and banged her head into the wall.
When the victim had asked Rees to call an ambulance, he had dialled 111 and "told them to come to number 6 -- and then you said **** you".
Police had come to the property and found the victim with bruising, swelling and redness to her face, and Rees told them he had done nothing, and it was just an argument.
Judge Morris said she had the "real sense" that Rees thought it was the alcohol that was at fault.
"It was you, Mr Rees -- an intoxicated you but you nonetheless."
She read a note from Rees, in which he said "when I pushed my partner" he was drunk.
"The law is very clear that I can't take that into account. You were the one who chose to get yourself intoxicated," Judge Morris said. The judge said the victim impact statement said Rees had apologised, and she had forgiven him.
"It is very common for victims to forgive. That's not to say they're not still at risk -- they are," Judge Morris said.
Referring to Rees' drug use, Judge Morris said: "As a man prepared to commit violence, it makes you even more dangerous that you are a user of methamphetamine."
Judge Morris sentenced Rees to two-and-a-half months home detention, saying he had already spent "considerable time in custody".
The judge ordered six months' post-release conditions including alcohol and drug counselling and a psychological assessment, and disqualified him from driving for 12 months on separate charges of careless driving and driving while disqualified.