A military man trained in covert operations stalked his former partner with such sinister creativity she told prosecutors it felt like "psychological rape".
Phillip David Burton, 41, has admitted stalking Brisbane businesswoman Margaret Lawson in 2017.
But Burton contests certain alleged facts in the case.
For example he does not contest going to her unit after being released from custody, but he denies ringing the buzzer to her unit.
That has resulted in Ms Lawson facing cross-examination by Burton's barristers in a closed court.
While the hearing was open to the public on Tuesday, the Brisbane District Court heard Burton allegedly signed Ms Lawson up to spam emails and contacted a computer hacker following their 2017 break-up.
He allegedly turned up at her workplace and messaged her clients to the detriment of her business.
Burton also allegedly abused her over the phone in an Irish accent.
"She describes it as feeling like psychological rape," the prosecutor said.
"She felt she was under attack or in danger everywhere and she spoke about how she didn't attend work for weeks, that she experienced sleeplessness at night."
The court was told Ms Lawson had struggled with leaving her home and visiting bars and restaurants she had previously frequented.
The court was told Burton had spent a total of 431 days in custody prior to the hearing.
The hearing is expected to adjourn to continue at a later date.