"how did having kids affect our marriage?" We bickere all the time for the first few months. Partly because my husband was working out of state and was only for 2-3 a week, and I was a walking zombie being a single parent the majority of the time. Plus, we had 9 years where we were childfree and just adjusting to a new little person was a bit difficult. We knew our son would change our lives, what we didn't know was that he would rock our world. And we've been happily rockin' and rollin' ever since.
When I was finally brave enough to admit our difficulties a older and wiser friend explained that what we went through was pretty normal considering our circumstances.