Michael Connon warned his terrified victim: "You think you've had a good hiding before? I'm going to kill you this time," when she finally plucked up the courage to walk out of their 20-year relationship.
Newcastle Crown Court heard the 37-year-old had left the woman battered and bruised during a baseball bat attack last October.
The couple had started arguing while drinking together when Connon snapped and followed her into a bedroom.
Prosecutor Michael Bunch told the court: "He began to punch her in the face and upper body, using two clenched fists.
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"He pushed her on the bed and started to strangle her."
The court heard Connon left the room for a short time during the attack, but returned armed with a baseball bat.
Mr Bunch added: "He used it to strike her twice to the upper left thigh and then left the room."
The court heard that three weeks later Connon launched a second attack when the woman was lying on her bed.
Mr Bunch said: "The defendant came up to her and started arguing, referring to her as a 'lying *****, and began to attack her.
"He punched her repeatedly to the face. He punched her to the legs."
The court heard in the hours after the second attack, in November, the woman packed her belongings and went to her mother's home.
Connon was refused entry when he turned up at the door and told his victim to go to the window.
Mr Bunch added: "She did so and saw the defendant outside. He was abusive towards her.
"He said: 'You think you've had a good hiding before, I'm going to kill you this time'.
"He said: 'I'm going to kill you and kill him', obviously suspecting she had been unfaithful."
In an impact statement, the victim said she was "terrified" of Connon and said: "I believe he is capable of killing me."
Connon, of Wynn Gardens, Pelaw, Gateshead, pleaded guilty to assault, common assault and making threats to kill.
District Judge Philip Kramer sentenced him to two years and three months behind bars, and issued a five-year restraining order to keep Connon away from his now ex.
The judge told him: "You seemed to think she was there to be attacked by you.
"Assaults of this type, in a domestic context, are always regarded as very serious.
"It seems to me there was an abuse of power. You were living in the same household and she relied upon you to be civil towards her."
Geoff Knowles, defending, said Connon has a good work record, has been in the same job for 15 years and could be safely punished and rehabilitated in the community.
Mr Knowles said Connon realises he must change his behaviour, and has accepted that the relationship is over.
He added: "He pleaded guilty, which saved his lady from coming to court to give evidence."