My birth plan was eight pages long. At 26, I hadn’t planned my pregnancy, so I was determined that our baby’s debut would be precise. Throughout those nine months, I read any parenting book I could get my swollen fingers on, dog-earing every other page. I considered whether our baby boy would be circumcised, how many months I would breast-feed, what preschool he would attend. I’d carefully carved out the details for any possible mishaps and milestones of our son’s little life — except for one. I never considered what would happen if I divorced the man who’d made me a mother.