I haven't been through it, as such, but to some extent I think I can understand.
In terms of finances, I was really shocked to find out this week, that when you have a nanny, it doesn't necessarily mean your childcare expenses double, or even increase at all...still can't get my head round it, but it's true (just in case you didn't know!)
My DH and I have been through some fairly difficult times when our DCs were small..he has been pretty rubbish tbh when it came to the hands on stuff (night feeds, though they were all ebf, getting up in the night when they were ill, taking turns at the weekend to get up early, changing nappies..you name it!) I was pretty unhappy at times, resentful and our relationship did suffer.
However, I was a SAHM, until about 20 months ago, and he had an extremely stressful job and worked all the hours God sent. I don't know how I would have coped if I was in a stressful job...we would probably have had less DCs and/or possibly even have split up, so I am grateful that things are as they were, because I wouldn't be without him or any of our DCs.
The thing is, things are very, very good now. I am more in love than I have ever been and he is a fantastic father and husband.
I suppose what I'm trying to say, is that, when you're in the thick of those sleepless nights, and up to your neck in nappies, it seems like it will never end, but you do come out the other end, and it's a small price to pay.
You know all this anyway, you've said as much yourself, I know. If there's anyway you can assure your DH that you will do the lion's share, would he be more willing to enter into ttc number 2?
Of course, you yourself might not want that, perhaps you only want to do it if you can be confident that he will pull his weight. IME, though, I worked through any resentment, and I'm so glad that I did, as we know have the family of 4 that we both initially wanted, and a very happy and equal partnership, too.
Good luck xx