As told to Ann DeGrey.

I'll never forget those long years I spent in therapy, digging through the mess my horrible stepdad left behind.

He married my mother when I was just nine, and it was all coercive control and financial abuse.

It became worse when I was a teenager. He'd dictate every little thing about my life; who I could see, what I could spend, even how I dressed around the house.

If I stepped out of line, he'd cut off pocket money or lock me out of decisions that impacted me.

He really delighted in making me feel small and trapped. It was worse for my mother, but, for me, the emotional side was just awful.

There were constant put-downs, gaslighting me into thinking I was the problem.

It took until my mid-20s to start healing, multiple sessions of therapy unpacking the self-doubt.

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By my late 20s, I was finally feeling good about myself. I'd landed a job as an interior designer, bought an apartment and just felt good about myself again.

That's when Tim* came into my life. We met through mutual friends and I just loved that he had a big personality, as I'm more of an introvert.

He was always cracking jokes and he had a very magnetic personality. Everyone loved being around him. He was a typical sales rep, with lots of energy and drive.

He was a very loving partner too. He'd often surprise me with presents, or special nights out at my favourite restaurants. He made me feel very loved and cared for. So I finally felt like I had the man I'd been waiting for.

I'd opened up to him about what I'd been through with my family and told him details about my stepdad's abuse. I told him that had made me cautious in relationships.

Tim listened closely, always looking into my eyes. He was a great listener and so supportive in the beginning.

He said he was very proud of me for dealing with my trauma, and he promised to be there and he wouldn't put any pressure on me in any way. It felt very sincere, like he really understood me.

As we got closer, I shared more details about how the isolation of my teenage years really had a negative impact on my trust. I also told him that while my step-dad hadn't sexually assaulted me, he had tried to several times.

Tim hugged me and kept assuring me that I was strong and that he was there for me.

So for a short time, everything seemed solid. We celebrated six months together, talking about our future plans. Both of us wanted to experience living overseas. Maybe in Europe, where Tim's grandparents lived.

But then things started to change.

Tim started staying late at work, talking about a new colleague named Gemma*. He'd mention her casually, saying she helped with projects. I didnn't overthink it because therapy had taught me to avoid jumping to worst-case scenarios.

Still, he grew distant, pulling out of dates we'd arranged or getting irritable over little things.

When I pointed it out, he brushed it off as work stress and I believed him.

The bombshell came a few weeks later.

I was at his apartment, charging my phone, when his phone pinged with a text from Gemma which said, "Thinking about you and thinking about last night. So fun, missing you."

I felt sick right away.

He was in the bathroom, so I went through his messages and found the proof I was looking for; they were clearly having sex.

It looked like it had been going on for weeks.

So I confronted him, trying not to cry.

But he didn't even try to lie. Instead, he turned it around, saying I'd been emotionally unavailable because of my past with my stepdad.

He claimed that baggage made me closed off, and he just needed comfort from someone who could be fully present.

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Gemma, apparently, fit that bill. I couldn't believe he was using my trauma, the very thing I'd trusted him with, as his excuse for cheating. It wasn't about supporting me; it was his way to justify stepping away from me.

I stormed out, thinking he'd follow me. But he didn't. The pain was dreadful. It wasn't just the betrayal itself, but it was about how he'd twisted my vulnerability into a weapon. He texted me something like an apology before I blocked him.

This experience threw me back into therapy for a while, sorting through the fresh wounds. But I learnt a few things too and realised Tim's actions were his fault and nothing to do with me.

Two years later, I'm in a much better place.

I've moved interstate and my career is thriving. I'm still single but I'm not in a rush to meet a new man. I've heard that Tim moved away from Gemma and onto a new woman.

No doubt he'll be charming her the same way. In some ways, I regret that I really opened up to him but I also know that opening up doesn't mean giving away your power.

The author of this story is known to Mamamia but has chosen to remain anonymous for privacy reasons. The feature image used is a stock photo.

Feature Image: Getty.