'I gave my boyfriend the keys to my apartment. It was the beginning of my nightmare.'

When Jessica* met Adrian*, she was only a few months out of a marriage marred by neglect, disrespect and loneliness.

She wasn't looking for another relationship, but Adrian was everything her ex-husband wasn't — present, kind, and hands on. He was also extremely into her.

"Unlike my ex, Adrian wanted to be involved in all aspects of my life," said Jessica.

"Sure, he was a bit full on, but it was just so nice to be with someone who cared about the decisions I made, and my children's wellbeing. Plus, he was just so kind and attentive in a way that kind of swept me off my feet."

Watch: Are you in a toxic dating situation? Post continues after video.

The relationship progressed quickly. Much quicker than Jessica would have preferred, but Adrian just seemed "too good to be true", and she didn't want to mess things up.

"About six months into the relationship, he gave me a key to his apartment, which I thought was really sweet. But then a couple of weeks later, he started dropping hints about moving into my place."

Jessica owned her own home, while Adrian rented his apartment. Both in their late thirties, Jessica assumed he'd chosen to rent for a few years following his own separation while he was finding his feet.

"Eventually, he asked me outright if he should sign over his lease to someone else and move in," Jessica said.

"Things were just so perfect. We had the perfect blended family. So, I said yes, and I was genuinely excited."

So, it wasn't long before Jessica signed over the lease and handed over Adrian the keys to her own apartment.

A single mum, Jessica was receiving some Centrelink benefits on top of her part-time wage. When they completed the mandatory forms, she discovered that not only did Adrian have no assets, he had no savings either.

"Honestly, he was just so amazing to me and my kids that, although I was conscious of it, I still didn't have any second thoughts. I was convinced we were a sure thing, and if things didn't work out, I believed he'd have enough integrity not to go after anything that wasn't his."

Unfortunately, once Adrian was settled in the home, his personality slowly changed. The kind man she once knew, began to disappear.

"After treating my children like his own for so long, he started being quite cruel to them. At first, it was subtle, but eventually it was so extreme there was no option outside the relationship ending."

By then, they'd been together for several years, so when it came to property settlement, everything was up for grabs.

"It turned out he did not have the high integrity I thought he would have, and he went for 50/50 in the property settlement," said Jessica.

"I wrongly assumed the property pool would only include the wealth we'd built together, but I was wrong. Everything was included, including my property."

"I was able to bump my share up to 60 per cent in my favour, but at the end of the day, if it wasn't for me, he would not have all that cash sitting in his bank account."

Inviting someone into your home can feel like the natural next step in a relationship, but as family lawyer John Patterson, from Patterson & Co Family Law explains, it's also one of the biggest legal decisions you can make.

"In Australia, de facto relationships are recognised under the Family Law Act," he said.

"If you live together for two years, or even less if there's a child or financial dependence, your partner may have a legal claim to property or financial support if the relationship ends."

It's something many people don't realise until it's too late. "I often see women who've worked incredibly hard to rebuild financial independence after a previous long-term relationship," Patterson said. "They're surprised to learn that simply living together can expose them to legal risk."

It's easy to assume that if one partner has no assets, there's nothing to worry about. But that's not how the law sees it.

"The absence of wealth doesn't remove the risk," Patterson explained. "Contributions aren't just measured in dollars. They can include things like caring for children, maintaining the home, or supporting your career. Over time, those contributions can be considered when dividing property."

In other words, even if your partner moves in with nothing, they may still be entitled to something if things fall apart later.

Patterson says protection doesn't have to mean mistrust. "Taking appropriate, proportionate precautions can actually strengthen a relationship if it's done with openness and respect," he said.

One key safeguard is a binding financial agreement, often called a "prenup" or "cohabitation agreement."

"This sets out how property and finances will be handled if the relationship ends," he said. "It must be drafted with independent legal advice for both partners, and particular care must be taken so it meets all legal requirements."

Handled sensitively, these conversations can create clarity rather than conflict. "In my experience, when couples approach it the right way, it fosters transparency and understanding," Patterson said.

Beyond formal agreements, Patterson recommends a few simple but effective measures: keep your finances separate, document your contributions, and clarify ownership of existing assets.

"If you're paying the mortgage, covering renovations, or funding improvements, keep records," he said. "These steps won't always offer watertight protection, but they can certainly help reduce risk and make things clearer if disputes arise later."

At its core, this isn't about expecting the worst, it's about valuing your peace of mind.

"Protecting yourself legally doesn't mean you expect the relationship to fail," Patterson said. "It means you're valuing your security and setting up the relationship on a foundation of fairness. Love and law can absolutely coexist, and when they do, both partners are freer to build their future with confidence."

*Names have been changed due to privacy.

The author of this story is known to Mamamia but remained anonymous for privacy purposes.

Feature image: Getty. (Stock image for illustrative purposes).