'How I discovered my dad on a dating app.'

As told to Ann DeGrey.

When our parents divorced more than 20 years ago, my sister and I were absolutely heartbroken. We were teenagers then, old enough to understand what was happening, but too young to fully process the betrayal. Dad had left our mum for a younger woman, a woman he fell in love with at work. But to make it worse for us, he didn't just walk out on his marriage; he walked out on our family.

We didn't see much of him after that. For several years, he ghosted us, aside from a birthday card once a year with a $20 note inside. Christmases passed with just the three of us trying to make the best of it.

But, slowly, we got on with our lives. Mum worked hard, rebuilt a home for us, and never once asked for sympathy. But she made one thing very clear: she didn't want to hear Dad's name again.

"Don't ever talk about your Dad in front of me" she once said.

Watch: The difference between emotional and physical affairs. Post continues after video.

Video via Mamamia.

Then, 10 years ago, he came back into our lives. It wasn't dramatic in any way; he just sent a text one day, asking to catch up. My sister Abby* and I were nearly 30 then, and the years had really softened our anger. I was looking forward to seeing him again, but it was more out of curiosity than anything else. So we met him near the beach for brunch and had a nice morning with him. He looked almost exactly the same; boyish, blonde-haired, still with that ageing surfer charm that had always made people forgive him too easily.

I don't know if we ever truly forgave him, but we let him back in. Slowly and very cautiously.

But Mum refused to speak about him, let alone see him. If we mentioned his name, she'd go quiet or leave the room. "He made his choices," she'd say. And we respected that. The idea of them ever reconnecting felt impossible.

Then, quite suddenly, everything changed.

Our aunt (Mum's sister) died quite suddenly. The funeral brought together people who hadn't shared a room in decades, including our Dad. He stood at the back during the service, being very quiet and respectful, but afterwards, he and Mum ended up sitting together at the wake.

None of us expected it; we could hardly believe what we were seeing. We thought it'd be awkward and tense. But somehow, they laughed and talked. It was like watching something out of a dream, or maybe a movie. A few weeks later, Mum told us she'd been seeing him again.

At first, Abby and I were stunned — but we were also over the moon! Mum had spent so long on her own, so many years with her guard up. If this was healing for her, who were we to stand in the way? Maybe people can change.

They started seeing each other more often. He took her out to dinner, or he'd come over to help with small repairs, or take her dog for a walk. It had been a long time since I'd seen her so happy. For the first time in a long while, it felt like our family might be piecing itself back together. Then I saw his phone.

We were at his place one afternoon, just the two of us, catching up. He left the room and his phone lit up beside me. I didn't go snooping. It just lit up, and there it was: a notification from a dating app.

At first, I thought it was a mistake. But when I opened the app, his profile was right there, recently active, filled with photos. I was absolutely furious!

I waited until he came back, and then I confronted him. I was calm but very direct. I asked him what the hell he was doing. He just gave me his usual smirk and said, "It's just a bit of fun. It's all harmless, [it] doesn't mean anything."

I told him it did mean something. It meant everything. And that he had two choices; tell Mum the truth, or I would. He said Mum didn't need to know. But I couldn't stay quiet. That night, I told Abby and we both sat down with Mum and told her. It was one of the hardest things I've ever done.

Mum just sat there, devastated. "That bastard," she said. She also spoke about leopards never changing their spots and the betrayal in her eyes said everything else.

After all this time, after everything she'd been through, she let herself believe in him again; and he broke that trust all over again. So now, we're all trying to pick up the pieces again. She told him she didn't want to see him again. But he keeps popping over, asking for forgiveness.

Only time will tell if she can actually do that. And I wouldn't blame her if she never did.

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

Read more of our Real Life stories: