SS, you and I have walked much the same road. Regarding the financial sitch, I'm not sure it's a good thing to put it off. I KNOW it's a big issue for you. To put it under the rug only to have it crop up again later might be worse than getting it out now. If it boils down to the fact that he can't get over his "guilty dad syndrome," is this a deal-breaker for you?
Alternatively, can you keep separate finances? You've been separated for some time, was that part of it? That was a big help in our sitch. When it was H's money and he couldn't afford it, his perspective changed completely. Ironically, then I was able to be the supportive and encouraging W, telling him to go ahead and give them his money if he wanted to, instead of coming across as the cheap, stingy, money-monger scapegoat.