'I thought I could trust my best friend with anything. Then I overheard her at our school reunion.'

As told to Ann DeGrey.

Isobel* and I met in our first year of high school and had been very close for many years. I'd say she was my closest friend in the world, up until I got engaged and she turned quite nasty.

I never wanted to believe she was jealous, but looking back, it's hard to ignore how differently she treated me after that.

Isobel had been on the dating rollercoaster for years, endlessly telling wild stories about first dates and flings. She used to say she was happy being single, but whenever I talked about my relationship, she'd either say nothing, or she'd make a joke about how boring and domesticated I'd become.

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It was rude of her, but I let it go. I figured she was just going through a hard time.

She moved interstate and, even with the distance, I still trusted her more than most people. So when I went through one of the most painful experiences of my life, she was the only person I told.

I'd hit a rough patch in my marriage and stupidly had a fling with a work colleague. It was at a time Andy*, my husband and I had a separation but weren't legally divorced.

Adding to the complication was that my fling, David, was married too.

And then I fell pregnant to my fling, who had no intention of being with me. I was just his side piece, and I was still in love with Andy and hoping we could work things out.

I really didn't know what to do and didn't want to have a termination, but then fate intervened and I miscarried. I was surprised about how devastated I was after that miscarriage, and it made me realise that what I really wanted was to be in a stable relationship with Andy and to try for a baby in another year or so.

Of course, I kept the miscarriage secret but stupidly confided in Isobel.

She was living interstate but regularly came to the city for meetings, so I asked her over one night. That's when I foolishly told her about the affair and also the miscarriage. She listened and told me my secret was safe with her.

Six months later, I was starting to move forward with Andy, and we were trying for a baby. I'd agreed to attend my high school reunion. Isobel was flying in from Brisbane, and I was really looking forward to seeing her, and having fun at the event.

It was a casual pub gathering and I loved seeing so many old friends. Isobel and I were with a small group of about five women chatting about our lives.

I got up to visit the bathroom and, when I returned, I stood a little behind the group as I was waiting to talk to someone else who was in a conversation with a woman I wanted to avoid.

So Isobel couldn't see that I'd returned from the bathroom. She suddenly brought up how difficult the past year had been.

Her voice wobbled and she started crying. Everyone stopped talking, and she said, "This year has been so emotional. Someone very close to me had a miscarriage. It was heartbreaking. She was involved with a married man and it broke her. Watching her go through that broke me."

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No one said anything at first. Then someone put a hand on her shoulder and said how strong she was for sharing something so personal, and they hoped her friend was okay.

I just stood there in silence; I couldn't believe my ears! The person she was talking about was me, of course, and she was deliberately making it about her. What kind of person does this?

I couldn't believe she had made my pain her tragedy. She cried harder than I had ever cried in front of her. People comforted her while I just walked away.

It like my grief had been stolen and repackaged for her to wear like a badge, like she was trying to impress these women she hadn't seen in years.

Later, I pulled her aside. I asked why she would share something. I told her in confidence. Her answer? "I didn't use your name. I was talking about how it affected me."

That was the last proper conversation we had. She sent me a long message a week later, saying she felt disappointed that I wasn't more supportive of her emotional process. I didn't reply.

I'm now a mum-of-two. Life is full and good and busy, but every now and then, I think about that night.

I think about how someone I trusted so deeply could turn something so private, into a scene designed to draw sympathy for herself. I've tried to move on, but it still hurts.

*Names have been changed to protect identities.

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