'Dear kindy mums who've judged me for being "the other mum", here's what I want you to know.'

After what felt like the millionth well-meaning mum approached me to congratulate me, I started to feel something other than the buzz of Prosecco creeping in.

By this point during the lunch, the vast majority of mums, dressed in their best 'going out dresses', were drunk and loud, and things were picking up speed. What had, at first, felt like an innocent "It's great you guys are here together," had become a vague wave in my general direction and the slurred words, "Good for you."

When Sarah* (the mother of my step-children) invited me to a school event, I jumped at the chance for a few drinks with her and an excuse for some time off from parenting.

Over the last nine years, our slightly uncomfortable relationship of ex-wife and new girlfriend had slowly developed into a friendship, even a sisterhood.

After all, we were raising the same children together. My step-kids are now in high school. Surely, I thought, this was going to be easier than the terrifying kindy mums.

The mums who'd turned their backs as I approached, or went out of their way to inform me what great friends they were with the 'real' mum — before pointing out boldly, that I wouldn't really understand because I didn't actually have kids of my own.

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I did have kids, my family just looked different to theirs. Perhaps this made them feel uncomfortable.

The truth is, I wiped bums, dried tears and got spewed on. I got up in the middle of the night because the door looked like a monster and lay awake worrying about milestones and messy friendships. No one ever dreams of being a step-mum. In the same way, no one ever sets out to get divorced. But, here we are — and these two little humans didn't choose any of it. At first, I hated it. I loathed how my plans would be changed in an instant by someone else, or how I had to fit in with his ex's schedule.

And when we did have the kids, it was a jarring contrast from the intoxication of a new romance — one where I was the centre of his world, now interrupted by two little people (who looked just like his ex) storming in and disrupting everything.

As someone without kids at the time, it was nearly impossible to step out of the way and admit that none of this was about me. And then, just like that, they would leave. Go back to their 'real' mum and I would feel relieved and lost at the same time.

Our home and life would fall quiet. We'd clean up the mess and put away the toys.

We'd have sex in the lounge room once again and stay out late partying with friends who didn't have kids. With every Monday came change and it was heartbreaking either way.

Nine years on, and there I stood with all the other mums, dressed up, champagne glass in hand and desperately trying to make small talk. Once again, I felt like an outcast forcing my way in when I simply wasn't invited. Was this just my own insecurities flaring up?

Most likely.

I reached for another drink from the makeshift bar. This is not a proven tactic that has ever worked for me, yet I continue to use it in awkward situations.

Safe to say, it did not help. I still felt out of place. And now, I was drunk.

Panic rising, I did what any tipsy woman in heels at a school fundraiser would do. I escaped outside and bummed a cigarette, that I did not want, off a stranger.

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This was not my finest hour — propped up against a cold brick wall outside a hall, full of women I desperately want to be accepted by.

Was this rock bottom?

No. This is just life. Beautiful, messy, confusing.

I remember him asking me so clearly, leaning over a romantic dinner, "Are you in? Or are you out?" I guess I didn't fully understand what exactly I was in for. But isn't that parenthood after all?

Perhaps I wasn't ever completely in.

Fuelled by the image of fairytale villains and popular movies, I punished myself for years, never fully allowing all the love in.

But I am not the villain here. It's okay to not be their 'real' mum and still love unquestionably, like a mother. I'm an extra hand to hold when crossing the road, one more kiss and a cuddle at bedtime, another cheerleader at a game.

The truth about being a step-parent is: you give all you've got, all the while feeling like an outsider, desperately trying to navigate boundaries you don't understand. With all of that, I've stayed for nearly a decade. Not because I had to, but because I wanted to — I chose to, over and over again.

Thanks to Sarah, we've built something real, not perfect, not effortless. But something rooted in mutual respect, shared chaos, and love for the same two humans.

It's not motherhood in the traditional sense, it's been restructured and rewritten.

I am proud to say that I am not their "real" mum. But they are my kids. I'm here, present, invested, tired, a little drunk—and real enough.