Robert Williams rowed with his then-partner after he went to the pub twice in a day, despite her asking him to help her recovery.
Portsmouth Crown Court heard the 24-year-old told her he was going to a bookies to put a bet on.
He was rumbled after the woman, dressed in her pyjamas and dressing gown, went to the pub in Portsmouth to find him there.
Matthew Lawson, prosecuting, told how the pair argued back to their home and Williams, of Fifth Street, Fratton, Portsmouth, had grabbed her wrist, pulling his fist back to strike her. Williams accepted this would have been threatening.
Mr Lawson added that as Williams shouted at her, he sprayed blood from his mouth on her as he was bleeding.
He added: ‘She was very vulnerable due to the operation she had and still being in pain from the discharge.’
Sentencing, Judge Ian Pearson said: ‘You’re a man who is clearly capable of being a bully.
‘On this particular day you showed a callous disregard to your ill girlfriend to go to the public house despite her illness.
‘To act in the way that you did when she was recovering only days after an operation was disgraceful.’
‘You are a bully in domestic violence situations. I hope your new partner takes full account of that.’
The judge handed Williams a three-month term suspended for two years with three-month 7pm to 7am curfew.
Williams admitted breaching a conditional discharge and received a one-month term consecutive to the assault, also suspended.
He must pay £150 prosecution costs and £250 compensation to the victim.
Mr Lawson said the victim had been with Williams since July 2015 having moved to Portsmouth to live with him.
He said she described him as controlling in their relationship and was ‘pushing her around and being abusive’.
The court heard the victim hit Williams during the incident, on December 5 last year.
He pleaded guilty to an offence of assault by beating at an earlier hearing.
Williams has 11 convictions for 17 offences.
One of the convictions related to an assault where he pushed his own father over during an argument, Mr Lawson told the court.
He admitted breaching a 12-month conditional discharge he received for that on November 13 last year at Portsmouth Magistrates’ Court.