He was approached by a female friend of his former partner who asked him to leave, the court heard, but he refused, swore at her and grabbed her by the hair before punching her in the face twice.
Prosecutor Garry Wilson told the court the woman raised her hands to protect her face but O'Donovan grabbed her by the arms, forcing her to the ground.
Walking further into the home, a male visitor asked him to leave as well. O'Donovan had also punched him in the face with a "clenched fist", causing him to also fall to the floor.
Mr Wilson said while the man was on the floor, O'Donovan had lifted his leg and stomped on the man's head causing a "bleeding nose".
Defence lawyer Ian Hard told the court his client was extremely remorseful for his violent outburst and had an alcohol problem that needed addressing.
He wasn't coping well with the relationship breaking down, the lawyer said.
"It was the end of the relationship," he said.
Judge Walsh noted O'Donovan had three previous convictions for assault between 1993 and 2007.
The victims had been seriously affected by the assaults, especially the man who had his head stomped on, the judge said during sentencing.
"I am convinced you stomped, that is very clear ... sometimes people get killed. It was cowardly to put the boot in when someone is on the ground. This victim was vulnerable ... your judgment was impaired by alcohol," he said to O'Donovan.
Violence was totally unacceptable, Judge Walsh said.
"What I must get across to you is violence is to be denounced."
He convicted O'Donovan on the two charges and sentenced him to nine months' intensive supervision with special conditions to undertake family violence and alcohol counselling along with ordering him to complete 100 hours' community work.
