Gentle sleep training methods?

Hello all. My baby is almost 5 and a half months and hasn’t been sleeping well since he was 12 weeks. He used to be a great sleep and had two 5-6 hour stretches a night.

Now his first stretch will last 2 hours, 3 if we’re lucky, and after his first wake he’ll be up every hour for the rest of the night. I pop him on the boob almost every time he wakes and he falls back asleep instantly. I don’t think he’s nursing because he’s hungry, perhaps just comfort. I attempt to put him back in his crib but after the second or third wake I’m usually too tired and we’ll just end up cosleeping the rest of the night.

We dropped our fourth nap about a week ago and he’s don pretty well with that but nighttime sleep hasn’t changed as a result. We follow WWs pretty strictly during the day, which are now 1.75,2,2,2.5 and only contact nap.

Also, 90% of the time I am the only one who can soothe him or out him back to sleep. My husband, god bless him, will get up frequently throughout the night to help me but baby will just scream until he’s passed off to me. He is instantly soothed with me which I don’t mind but it gets to be a lot when I am the only one that can put him down for a nap or back to sleep.

With each night that passes I’m considering sleep training more and more. I’m just here with hopes that gentle sleep training can be successful. Please share with me what you did you gently sleep train. Or if/when your LOs sleep just improved on its own.