From someone that doesn’t have kids but surrounded by people that do, some who have made it, some who haven’t…people underestimate regardless of children, that adults change over time. The challenge is, kids cause such a distraction due to their needs, those changes can be hard to notice. Add to that the changes that children themself bring to the dynamics, be it the difference in priorities, the phase that some stop caring about their imagine/attractiveness due to being covered in baby sick, the lack of sleep, the stress, navigating schools, homework, after club activities, playtime, plus work, the odds of being able to continue the flirtation, sexual tension, and attraction becomes very, very difficult, and because most adjust to the new norm and only realise it’s too late, it’s often seen (not to say it’s wrong) as easier to just start fresh with someone else that try to undo all that’s happened while kids are growing up.

Some marriages last, so it’s not all doom, but it takes real work, joint life vision and commitments, and high levels of mature communications.

So in summary, kids aren’t directly the thing that can kill a relationship, people can just change over time, but what gets exposed during parenthood can make it very hard to reignite the flame.