I don’t know how to phrase this correctly, so I apologise if this comes out a muddle, but please be mindful of who you are taking to about your wife and the levels of input from others.
When our second was little (similar age gap), I just wasn’t sleeping, for months. I had some sort of insomnia I think. It was super, super tough.
But my husband then went and asked some of his friends (who were a LOT older than us, with teenagers or older children).
They all said the usual ‘it will get easier’ etc etc, but in the moment, that just made me feel like shit. I didn’t want to hear that in 2 years things would be easier, I could barely think about the next day!! I didn’t need fixing, I needed someone to take the baby for a few minutes and let me rest or spend time with the older one, or whatever.
I needed practical, hands on help, and not to be made feel like I was the problem or not coping or whatever.
What I’m trying to say OP is that when you obtain a variety of external opinions, it muddles your thinking about how things ‘should’ be rather than looking at how they are. And so skew your ability t deal with what is actually presented rather than trying to achieve what other people will tell you it should be.
Good luck!