I run a site about baby sleep, so people assume my own children slept by the book. They did not. We bought the crib early, put it together, made the bed. My daughter slept in it for fifteen minutes - and then not once for the next six months. Later it worked, but only for naps…
Night waking in the first year is ordinary physiology, so sleeping "like before" is off the table for a while. What helps is unglamorous: catch sleep in short pieces during the day, split the nights honestly with the other adult, and let the flat stay messy. Sleep comes before…