@Snowfl I haven't rtft bit I've read all your posts, and the thing that jumped out at me was you saying you feel constantly disappointed by him. (Or similar) that really resonated with me. I split up with my husband, when I had a 2 yr old and 9 month old. I was terrified of doing it alone, until I realised that I WAS doing it alone.
And doing it all yourself, with no one to even talk to, is a bloody huge improvement of the constant disappointment of him not lifting a finger.
I am also better off financially, working part time and receive tax credits, than when he was here.
If you WANT to do less hours/take on more childcare, then he needs to work more. Simple as that.
It's bloody ridiculous, but I think you need to sit him.down and lay it on the line for him. He needs to be able to do this stuff. Write out a more detailed routine, along with a really basic timeline - 10am nap, wake up, nappy change, 12pm lunch and drink, 1pm play 3pm walk/nap in pushchair. However you do it.
Tell him, the child is crying it's because of nappy/hunger/thirst/tired. Check those first. Give him strategies for when dc is upset. My dc1 would always be distracted by looking out of the bedroom window. Lots to see. He CAN do this, and should want to learn.