'I was a step-mum, but now I don't know what to say when people ask how many kids I have.'

When people talk about breakups, they usually mean the end of a romantic relationship. But with some relationship breakdown, the loss goes far beyond your former romantic partner.

No one really prepares you for the painful loss that comes when a blended family breaks apart. When you fall in love with someone who has children, you know it will be complicated.

You understand there are boundaries and histories, and that the love might take time. But what you don't always realise is how deep that love can become until it hits you, or how invisible the loss will be if it's ever taken away.

For years, you show up. You learn favourite meals and bedtime routines, birthdays and inside jokes. You attend school events and sports events and you build a relationship that feels every bit as real as any biological bond. Until one day, it isn't.

When the relationship ends, the world tells you to move on. But moving on from children who still feel like your own, isn't as easy as it seems.

You miss the sound of their voice. You go to buy their favourite snack, before remembering you don't need to anymore. On their birthday, there's a deep pain in the pit of your stomach you can't escape.

Because this is a breakup you can't explain. And there's no word to describe being a former step-parent.

Watch: Who's looking after your kids? Post continues after video.

Relationship counsellor Susan De Campo says this kind of pain is both common and rarely acknowledged.

"If you've enjoyed a loving relationship with your step-children, then losing them can be totally heart-breaking," she said. "You've gone through the process of getting to know them, of giving and receiving love, and then it suddenly becomes nothing."

That "nothing" can feel incredibly painful. One day you're part of their lives, packing lunches, helping with homework, and driving them around, and the next, you're not.

There's no gradual fade or soft landing. The connection you built is simply taken away.

De Campo describes it as a form of ambiguous loss — a grief for someone who is no longer in your life.

"It's a dog's breakfast of incredibly painful feelings," she explained. "It's not a neat stage process. The emotions ebb and flow for way longer than anyone tells you."

What makes this grief particularly cruel is how invisible it is. There's no ritual or recognition for losing stepchildren. And very few people understand.

"It's also a kind of disenfranchised grief," De Campo said. "The relationship was real, but society doesn't recognise the loss as real. You don't have the right language or space to mourn."

And then there's the guilt. When you still want to be in their lives, but you know you can't.

"When a breakup is acrimonious and your ex has no interest in maintaining contact, you're powerless," De Campo said. "And some people even use the loss of contact as punishment."

Listen to this episode of Parenting Out Loud. Post continues after podcast.

For many step-parents, that loss can also shake their sense of identity.

"If you've been a step-mum for years, your identity as a caregiver has formed," said De Campo. "Having that suddenly taken away can feel brutal. It's a secondary loss, the loss of who you were because of them."

It's hard to explain to others how it feels to lose children who were never technically yours. You might still keep a few photos tucked away, or a small gift they once gave you. But when someone asks how many kids you have, you hesitate, because you don't quite know the answer anymore.

So how do you move through something no one sees? De Campo's advice is to simply let yourself grieve.

"Acknowledge that it's incredibly painful," she said. "Give yourself permission to feel sad. Be patient and remind yourself that you can choose to be gracious and self-caring."

Some blended families do manage to maintain relationships after separation, but, De Campo admits this is easier said than done.

"That requires everyone to be emotionally mature and respectful. Often, that's not the reality. Kids can get caught in the middle, and continuing contact just isn't healthy for them."

In the end, it's about love without possession, wishing them well, even from afar.

"Recognise that the grief you feel speaks to the love and connection you shared," said De Campo. "Give yourself as long as you need. And energetically, send them all the best wishes in the world, because that's what's best for them, and for you."

Feature Image: Getty. (Stock image for illustrative purposes).