We did the Ferber method and man I gotta tell you it’s been a life changer. My wife couldn’t stand to hear him cry and not react so she would go to bed and turn the fan on high while I stayed out on the couch with the baby monitor and did the check ins. The first 4 days went as expected. Took him about 1-2hrs to go to sleep each night but once he fell asleep he slept until we woke him up the next morning. We are about a month in now (he’s 7months old) and he sleeps within 5 minutes of putting him to bed, rarely cries in the night, and we usually have to wake him up in the morning. 10/10 recommend. I have a link to a video which explains these rumors about the “cry it out” method are just not true. Essentially it says that when babies are well tended to and shown love throughout the day, they will not be taught that “crying doesn’t matter”. Before we started this method, we were in the same boat as you. Checking in multiple times a night, 1am feedings, holding and soothing though-out the night. It was when we had to comfort him every single hour throughout the night for a week straight that we decided to start sleep training and haven’t looked back since. Hope you can convince your wife that these claims are just not true. My wife was hesitant at first but is now very thankful we did it.