Violent Lee Chugg fractured his partner’s jaw in two places with just one punch.
Michelle Blade was left having to eat liquidised food through a straw for six weeks and underwent surgery to put metal plates into her face following the attack on May 29, this year.
Chugg, 35, was jailed for 20 months at Gloucester Crown Court during his 67th court appearance.
Prosecutor Mark Hollier said the couple had been together for a number of years and Chugg had was a drug user and alcohol dependant.
He said he had previously been sentenced to nine weeks in prison after head butting her at Gloucester Railway Station in May 2013.
In a victim impact statement, Ms Blade said she was in hospital for three days following the attack.
She said: “I am not going to lie and say I’m scared of him when I am not.”
But the court heard their relationship had come to an end, but she would remain in contact with him and visit him while he was in prison so he could see their daughter.
Defending Sarah Jenkins said: “It was a single punch and there was a lack of premeditation. It was a moment of madness in a background of some disputes in the days leading up to it.
“He was on a methadone script and had been drinking heavily.
“She had refrained from substance abuse for some time, but took a heroin over dose and social services had become involved - it was taking its toll on both of them.
“He had got back in touch with his estranged sister that she did not like and he hit her while his phone was in his hand.”
Appearing from videolink, Chugg, told the court: “She was beating me beforehand.”
Mrs Jenkins added: “He is now far from drug use. He tells me he is 35 and this is the strongest he has been in terms of drug and alcohol use.”
Judge Jamie Tabor QC jailed Chugg of Magdala Road in Gloucester for 20 months after he pleaded guilty to causing Ms Blade grievous bodily harm.
He told Chugg: “Many of your crimes no doubt have been to feed your drug habit, but you have been before the court for violence.
“I don’t detect a great deal of remorse from you, but you have taken this opportunity to clean yourself up.”