Things deteriorated after a death in Jon's family.
"Obviously there was a bit of depression going on there, which I could fully understand. But then he got into drinking and taking drugs, and that's when the abuse set in."
He became paranoid.
"If I came home from work he would go and check my car to make sure no one else had been in the car. He would come to my work to make sure I was working.
"He played mind games and used my past mental illness as a weapon against me. He would constantly belittle me and exert his dominance."
At one point, Maria's father tried to step in but Jon became violent. "From then on, he would do things like making me sit in a chair and it could go up to three hours where he would just yell at me constantly. It would be something like, 'Who were you f****** seeing today?'
"If I tried to move - he never hit me, but he would hit around me. He broke his hand on the door."
The turning point was a drug bust at the house. Jon was arrested.
"I thought, 'This is it, I'm going to do it.' So I tried to say to him, 'I don't want you back in the house'," she said.
He moved out for a week, but the judge bailed him to the family home so he came back. But Maria did get him to move out again eventually.
He continued to harass her with texting, phone calls and abuse.
"The detective from the drug case rang me to see if I was okay. It took me off guard and at first I told him everything was fine," Maria said.
Later she agreed to meet him. "He said he knew something wasn't right just by the way I spoke in the house the day of the raid. He put me in touch with the police protection unit and I began a safety plan."
Maria attended courses at a women's refuge. She is now studying psychology and has a goal to work for a refuge or a women's prison.
To get help
Women's Refuge: 0800 REFUGE (0800 733 843)