It had plenty of risks before too. Doing genealogy, e.g. of one of my great-great grandfather's children, several died young and left behind children, some ran away from responsibilities (one child - my grandmothers first cousin - ended up in care and was adopted because her mother was too poor to care for her and her dad ran off to the US with his brothers, and we didn't learn she existed until a few years after she'd died) or were forced to work abroad for years at a time. Of 12 or so of his children, I think only 4 were in their children's life until they reached adulthood, and at least one of them was a single parent because her husband died young.
The same great-great grandfathers second wife likewise "lost" a brother that was almost certainly taken into care while she and her older brother were left to fend for themselves as teenagers after being orphaned when their father died after having cared for them alone for a few years after their mother died.
My grandmother's mother - married to one of the children of the same great-great grandparents - lost contact with her siblings in her early teens when they were all taken into care when her dad proved unable to deal following her mother's death. While she found a couple of her sisters again later, her dads failure to cope means even now we've not been able to figure out what happened to the rest of her siblings.
While divorce is more common, abandonment, be it intentional due to the difficulty of obtaining a divorce, or unintentional (poverty, disease, death), or absence for noble reasons (e.g. going off to earn money to support the family) still left a lot of people raising children on their own in often awful conditions.
There's a marked increase in the number of situations like that for each generation further back in my family tree among the people I can track.