Hi everyone, sorry for late reply and thanks so much for writing back. Your comments have all made me think and the supportive ones have been very helpful.
Just to write a bit more. I was very emotional last night. Baby did eventually settle with his dad and slept in his cot for another hour before coming in with us.
DH is a good dad and was in with DS the whole time, holding him and singing to him (this is how we've been sleep training, DH does night wakings, rocks/songs him back to sleep and puts him back in cot; repeats).
This had been working when we first tried it. We were down to one night waking, at about 4 then baby would come into our bed, have a quick feed then sleep until 7.
Then my husband injured his arm and we both got norovirus
so it all went to pot, I did some night wakings and fed him.
The problem is I just can't settle him without feeding him.
The reason we started sleep training was that DS was waking between 8-10 times a night and nursing and I was becoming unable to handle it and it was impacting on my parenting in the day times as I was so exhausted. DH was worried about me and also exhausted and so we decided to try something (albeit a little reluctantly on my part).
The HV also recommended this approach of sleep training.
I am going to take on board the 4am advice though. I had though going from constant feeding to non would be too much for him but it makes sense that I am making it more difficult for him. I will cut them out until morning (6am) and then get up and feed him:get up with him.
I think it's harsh to say that I am damaging him. But I admit the way I wrote the message made it seem like DH is an a hole. He isn't I promise, he's just trying to stay strong, and I know I can make things difficult when I change my mind. I didn't want to go in as I was worried it would negatively impact my baby and make him cry for longer next time to get me.
My problem now is that he also has a cold and I'm wondering whether to take people's advice and scrap the sleep training for another while and then start again from scratch.
Also, he has never been left alone to cry (maybe that's the problem 🤷♀️).
I'm still so confused. I feel like my instincts are different to my common sense. In the lights of day it seems easier. But in the night everything tells me to get him.
Last night was the longest he's cried (he usually resettles in 10 mins max!) so it got to me more.
Sorry I've written another essay! Thank you again to everyone who wrote back I very much appreciate every input x