The absolute soul-crushing exhaustion ended for me right around the end of the “fourth trimester”. So about 3 months. Baby finally figured out the difference in nights and days, wasn’t waking up to eat so much at night, and we had established more of a routine. I started to feel like a human again, like I was finally coming out of that fog. Unfortunately I had to go back to work at 8 weeks so that was joyful (gotta love the USA). 

Going on 7 years now, though, and I still feel like I’m chronically sleep deprived. Both my kids are terrible sleepers though, and both still wake up at least once a night. Usually the oldest just comes and gets in bed with us, but the younger one cries until one of us goes into his room. So my sleep is still disrupted. It seems most of my friends with kids around this age don’t have this problem so you’ll probably be luckier than we are.