@Summer I've just tried to reply a few times as tactfully as I can without offending you re your DH.
I know how much you care for him but heck girl it's time to put your needs first. It's incredibly tough because in theory fighting for his children will always come first, if he is a good father, even over the needs of a new partner. It's about striking a balance and seeing that your needs are met too. And like you said, he has assets he can draw on to help you/him.
Counselling sounds great. Hopefully you can weed out the root of the problem. If you had to chose between a (birth) childless life building on your relationship with DH or life as a single mum...do you know which one you'd chose? I'm not saying it would come to that of course, I hope you can have both DH and bubs.
This is the bit that I was clumsily trying to write. If I was you, I'd be setting aside some ED eggs and fertilising them with DS, just in case. Even if it was only 3 eggs. It just gives you options when you pay the initial big lot of money. I hope that doesn't sound too callous. It comes from a good place. Promise.