And do we judge them more harshly for it?
Women are in the minority when it comes to parents who leave their children.
According to the Australian Bureau of Statistics, 81 per cent of single parent families were also single mother families - meaning fathers were more likely to be the ones living away from their kids.
Both its rarity and a variety of social norms and expectations around motherhood have contributed to its persistence as a taboo of modern-day parenting. It is rare to hear the voices of women who choose to leave their children in the primary care of a partner or relative - something this week's Insight seeks to address.
Is their decision to leave done out of selfishness, or selflessness?
In 2012, Kristal Kinsela found herself in an irreparable marriage with her partner on the NSW north coast, with their two children. The couple split and shared care of the kids equally, but Kristal found her career stalled and life isolating in the coastal town. Career opportunities and her large, Indigenous family pulled her back towards Sydney, and she was conscious of the impact the back and forth between parents was having on her son and daughter.
"I couldn't live in this limbo any more," she tells Insight's Jenny Brockie. "I felt like I [wasn't] fulfilling my life. I've done something with myself, I'm being successful. I've broken down the cycle of welfare dependency, I'm trying to do something with my life and you know ... I'm trying to teach my kids the right way."
She made the tough choice to leave the kids in the primary care of their father, believing that their presence between two parents in conflict was unhealthy.
"I want them to feel safe and secure and stable in one environment," she says, "and I knew that they would have that with their dad."
Melissa Collins similarly recognised stability in the home was more important for her children than herding them between places. She was unhappy in her relationship with the kids' father, and felt that the country life they were living was not for her.
"When I told him that I was leaving he begged me not to take them," she says. "It had never occurred to me that I would ever go without them. And yet in that moment I thought, I could do this."
Looking at the established life and structure her boys had with their father, and believing he was more capable of providing that, she left for Brisbane.
Looking back, she says the decision was, at times, "utterly debilitating"; she would yearn for the 'everydayness' of living alongside them. But she knows the kids are happy, and stands by the decision.
For Mazuin Claude, she knew her battle with mental health was no place for children. As her mental health deteriorated with bipolar disorder, she realised she could not be their carer and in 2012, she left.
"I felt like I was actually going to ruin their childhood if I had stayed with them any longer," she says. "If I had been that kind of negative influence, because they were just so young. I felt like I was going to pollute them and I didn't want them turning out like me."
"I was torn [with the decision], of course I was really torn ... but I knew that I needed help."
With that help, she is now able to see them once a week and forseees a future where she might live with them again, when older.
Do we judge women more harshly for leaving?
For the women on this week's episode of Insight, facing the judgment of their peers and family has been difficult.
"I feel like it's like society that tells us ... that you're supposed to get married and have the house and do all that. Well I did all that as well and that didn't make me happy," says Kristal.
"I think it's powerful to be breaking down the stereotypes and the stigma of what [a woman's] role as a mother is supposed to be or what it's supposed to look like. Things are evolving."
The stigma around mothers walking away from their children is likely linked to the status afforded to the mother-child relationship. And yet studies have shown that fathers develop antenatal relationships with their unborn children in similar strengths to mothers, and also experience the same release of the 'bonding hormone', oxytocin.
It's powerful to be breaking down the stereotypes and the stigma of what [a woman's] role as a mother is supposed to be or what it's supposed to look like.
Dr Anne Sved Williams, a perinatal and infant psychologist on Insight this week, says there's been no research to show the impact of mothers leaving is worse than if a father leaves.
She also points out that in non-Western cultures, the biological mother is not always solely responsible for parenting children; the nurturing role is shared among family and relatives.
"What children need is one person at least who keeps them in mind and they need some peace and harmony in the house to bring them up," she says. "So it doesn't have to be the mother, it can be a great father or a great grandparent."
Still, the pressure can persist.
"It's hell," says Melissa Collins. "I've lost friends, I've had family members question my sanity, my ability to do it."
"[But] it was the right thing to do. It was absolutely the right thing to do."
Find out where these mothers are now, and hear their full stories on Insight's episode, Mothers Who Leave.