I have a grown up dsd who was two when I met her father and she can't remember her parents as a couple. We are really close and she's always lived with her mum but lots and lots of contact with us.
She was genuinely shocked at about four to find out that her parents were once a couple lol and was curious.
Her dad explained that once , her mum and dad were best friends, but now they are just ordinary friends and him and I were now best friends and her mum and dear stepFDAd were now best friends.
She was perfectly happy (after a few questions about where her step dad and I were when her parents were married! ).
When her mum got pregnant her dad did not want a baby
She's never asked anything since and we've fortunately been able to keep things amicable among the four if us in the parental role fir her sake and always pulled together.
Me and her dad split last yr but she and I have remained v close. She's very well adjusted and I'm still in regular touch with her mum . Me and her dad are nit on good terms but she knows we all love her and have her best interest at heart.
Her mum and dad have not always been on good terms in fact he hated her at one point.
Hope this goes to show complicated circumstances don't need to mean problems for the child