"An open letter to the mother of my step-daughter".

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You left your husband, you packed your bags and let everyone know you could do better so if you could please remind your friends and yourself this occasionally I’d appreciate it.

I understand that no mother wants another woman around their child, sharing special moments, braiding their hair, reading them bedside stories. No mother wants their child to fall in love with a woman who represents what was their world.

I am sick and tired though of you, your friends and family treating me poorly. You were divorced for three years before I came along and separated for four. I asked my partner again and again had he done everything in his power to try and make your relationship work for the sake of your child.

He assured me you’d left him, you’d done marriage counselling, you even tried again and that failed.  So I’m not sure what you thought would happen. Did you think he would always be yours?

A step-mother’s confession.

I came into this world and embraced your daughter. I kissed her goodnight while looking at photos of you and the day she was born. I sat at the table while she told stories about you and her dad, about wedding photos you show her now and then.

I comment on how beautiful you are while she would make jokes about how her (a seven-year-old) and I are practically the same age despite me being 28. I smiled as she let me know how funny her mum and friends found my car, how silly I danced in a debutante video they found.

I walk down the street where grown women find it acceptable to stop your daughter and have entire conversations without acknowledging me. Women who walk off when I arrive at barbecues as if I’m a home wrecker, who ask my partner how you’re doing as I am standing next to him.

So to all of the first wives' club women and subsequent minions out there I say check yourselves. Try for one minute to imagine what it feels like to come into the world of a divorced man with a child.

Even when I had my first child, it was the second to come into his world and his family's. Whilst other first time mums are laying low the first few weeks I was making school lunches and doing drop off and pick ups.

“To my daughter’s step mum: I never wanted you here, but this is what I have to say.”

I care for two children in this home but on special occasions or school events I am an afterthought. I understand and expect this as I'm not her mum. But do you know what it feels like? To see everyone saved under her contacts even the cat and dog but not me?

To push a pram in the sand to cheer her on for cross country and she runs straight past me to you and her dad. I am no threat to you as I am not her mother, that beautiful role is yours.

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The least you and your friends can do is thank me for loving your daughter and doing my very best to care for her in my home. A home that was yours until you decided you didn't want it anymore. Don't blame me when you want to have joint birthday parties and lunches and I remind you you're divorced.

How can you expect to come into my home when you won't acknowledge me down the street?

I write this article to encourage all the other women in the same thankless position as me to keep doing a wonderful job.

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To stay afloat despite the poor treatment by misguided women, and to remember in the end it is the child that matters most. To all of the ex wives, don't be consumed by bitterness. Don't hate someone for filling a gap you left open and don't hate on someone for loving your child.

Mamamia's Infertility Week shines a light on the joy, the pain and everything in between when it comes to creating families. To read more from Infertility Week, click here.

The author is the mother of a 10-month-old and step mum to a 10-year-old. She is also a freelance journalist.