I didn’t expect the ER to break me. It was 2 a.m., and I was slumped in a plastic chair in the same pajama pants I’d given birth in, cradling my three-week-old. Olivia was burning up and screaming so hard her voice went hoarse. I rocked, whispered, fumbled a bottle with one hand. My C-section incision throbbed. I hadn’t slept...