She described transforming from "outgoing, bubbly and confident to a feeble shell of a person ... consistently on edge, waiting for the next mistake".
The second victim said she was prescribed anti-depressants during their relationship and the defendant persuaded her to come off them.
When she did, her self-esteem suffered and she became even more vulnerable, she said.
"You've had a profound effect on the lives of two women and their families," Judge Michael Crosbie said.
The court heard how on one occasion the man had demanded sex from his first partner when she was physically unwell.
Despite her sobbing and her placing a pillow over her head, he still forced her into a sex act.
The second woman told police of waking up in bed to find the defendant astride her "as he bared his teeth ... with his eyes bulging".
He forced himself on her until she escaped.
The defendant was originally charged with rape but the allegations were later downgraded.
Defence counsel John Westgate said his client was "panicking and desperate" after police first interviewed him.
The defendant called one of the victims and pleaded with her not to make disclosures about non-consensual sex.
When the woman said she would not lie to police, the man asked her to think of their children.
Further conversations, which were intercepted by police, involved the defendant refusing to sign legal documents relating to their financial affairs "until I know I'm safe".
"You not only tried to manipulate them but also the criminal justice system," Judge Crosbie said.
The offending did not end even when the defendant was remanded in custody, where he has spent the last three years.
During 2017, he called his son and his parents from prison, urging them to make accusations about his ex-partner stealing from her workplace.
Repeated requests of his father reduced the man to tears, court documents revealed.
Westgate said his client's problems stemmed from a traumatic head injury, suffered more than a decade ago, and a harmful pattern of drug abuse.
"After that incident his life slowly came unravelled," he said.
The judge said it was unclear how much of the offending was attributable to the head injury but noted the man did little to help himself.
"The combination of illicit drugs with such injuries can be a potent cocktail," he said.
Westgate said his client was committed to turning his life around while behind bars.