When Rachel's* boyfriend told her he would cut her into tiny little pieces and bury her in the garden if she ever left him, she thought he was joking.
When he gave up work to keep an eye on her she just thought it was a possessive period he was going through.
Then he started checking her email, and trying to stop her from spending time with her son.
"I thought Oh My God, not sweet, quite scary. I saw alarm bells going off."
But it wasn't until a friend confided in her that she'd once gone into a refuge after experiencing domestic violence with a controlling partner that she ended up phoning Women's Aid to ask for help.
The 38-year-old, now a company director, says that was the moment she realised she was in a dangerous situation.
"There wasn't any violence as such but it was psychological," she tells the Huffington Post UK.
Rachel is one of the many women who have experienced a controlling relationship which is emotionally, not just physically abusive - as covered in the government's new definition of the crime.
"When I met this chap he seemed very lovely, he was nice and dependable, which is what I was looking for. Someone I thought I could rely on," she said.
"Pretty soon he started to display rather strange behaviours.
"He gave up work because he wanted to be around me all the time.
"He would start going to bed at 2 or 3am, he wouldn't get up until mid-morning.
"People would ring and he wouldn't pass on the messages. He was trying to get me away from other people.
"We were sitting talking one day and he put his hand around my throat. He would try and get my son to go off and do things on his own. I was thinking to myself 'this is not very healthy'."
When Rachel rang her local refuge about the situation they said she could have a room immediately. The successful business woman found she was also given the right support to get her life back on track.
"No one should stand for abuse. I think that people need to understand you can move on, you can move forward after domestic violence," she says.
The advice she'd give victims now? Leave. Once Rachel did, she set up her own business and gradually found a new partner.
"It took me three years, I think it's really difficult when someone has behaved in such a bad way. You get a little bit super sensitive about things. Men can sometimes see like a different species.
"I thought it doesn't matter what's happened with this guy. I just have to show my kids that even though things happen it doesn't have to ruin your life."
"I would say it's not a good idea to stay. You have to make the sensible decision. I think it's difficult when you care about someone. But people generally don't change. if that's how they're going to treat you, that's how they're going to treat you."
*Rachel's name and some details have been changed to protect her identity.