I just wondered if it was common. I was full of the joys with my partner all the way through pregnancy and childbirth and a couple of weeks after my daughter was born we were back to having sex but something had changed. Of course we were tired and stressed with a newborn but it soon became clear that we had completely different parenting styles and we couldn't stop it affecting our relationship with one another. The sex stopped (apart from once or twice a year when drunk after I'd had a paddy about the lack of sex and then it was just a quick bang) and we grew apart. We were completely unlike our loved up state during the exciting period of pregnancy and before. We both wanted a child and I believe we didn't think it through properly. We made no commitment to one another with regards to getting through tough times after she was born. The changes she made to our lives were difficult to cope with.
Today we live apart and our daughter goes back and forth between us. We still parent differently and cannot talk to one another much before erupting in an argument, even though I've changed my behaviour to allow for his i.e. avoiding triggering comments and abstaining from trying to parent our child whilst I am in his home.
It's a damn shame as I'm not sure either of us will find another person to be with. We briefly considered trying again when things had been fine for a while, but I threw that idea away after another unexpected argument which was the result of finding out he was repeating past mistakes.
I worry about the way my daughter will grow up. She is only 4 and we split up when she wasn't yet 2 so it's all she knows, but she has to make decisions she shouldn't have to make at this age.