I'm wondering about this relationship. Did she pretend she didn't want kids and move in with him anyway, in the hope that once they started making wedding plans, he'd come around? Or that once the 'we-re-getting-married ball starts rolling downhill, he will knuckle down and go with it?
As for this, I'm with you in the shyeah department over this:
"I would have actually broken up with her last night, I think, but then she said that if I was really going to insist, then she'd be ok with not having kids."
This wouldn't be a good enough answer for me. I would need someone to not want kids on his own, not just because he's giving them up for me. I don't want that burden, thank you very much.
I concur that it sounds like she's saying what she thinks he wants to hear.
She sounds like a double rubber gal. The guy should definitely get the snip before marriage and see if she sticks around.