Violent Christopher David Monks, 28, of Enderslea, Parkside Lane, Nateby, near Preston, was jailed for 14 months after a judge was told he slapped the new mum across the face during the row as their eight week old baby was sleeping in her car seat.
Prosecuting, Paul Cummings said during the incident on December 1, he trashed their home, smashed the TV, and photo frames, and accused the woman of plotting to leave him, before hurling his victim's handbag through the front door and kicking the baby seat through it.
The victim, who suffered bruising to her face, did not press charges at the time.
Preston's Sessions House Court heard in a second incident on December 22, jealous Monks attacked a man in his friend's home after he revealed the woman had texted him in connection with doing some plastering work for her.
Mr Cummings said: "It had the effect of upsetting the defendant, the complainant says he didn't even manage to finish his sentence before he lunged at him.
"He grabbed him with both hands around his neck, he thought his neck was going to snap.
The man was knocked unconscious and suffered a gash to his head, but managed to get out of the house.
On January 20, the couple's relationship had improved, the court was told, and they decided to go shopping with the baby and Monks' young daughter from another relationship.
But as the family drive up the A6 at Catterall, Monks asked to 'borrow' her phone to make a call.
He then checked through it and accused her of deleting messages and 'hiding something from him'.
Mr Cummings added: " He then lunged forward and put his forearms around her neck and forced her back into the headrest.
"She was struggling to breathe and to see, and afraid for everyone in the vehicle. She thought she was going to crash. She braked hard and came to a stop."
The woman later reported both incidents.
Monks admitted two assaults on the woman, and causing actual bodily harm to the man.
Judge Ian Leeming QC imposed a five year restraining order.