Hi Sparkler. I was in this position as shortly before birth of ds2, dh and I discovered that I definitely wanted one more and he definitely didn't.
For reasons that made sense at the time, we agreed not to talk about it until ds2 was one. And for a year, I guess that I thought dh would give in and he thought I would. So shortly after ds2's first birthday, we went out for the day for a long walk (just the two of us) to talk about it. It wasn't pleasant, we didn't argue but there was absolutely no way we could agree.
I started to sleep badly as I realised there might not be any more babies, and cried a lot though always tried to hide this from dh. Eventually, we started to discuss how unhappy our decision, or lack of decision, had made me. And he gave in. Unbelievably and quite unexpectedly. He said I was more unhappy than he would be if we did have another. And we talked it through, and he agreed that he would be happy if we had another baby, because it would make me happy.
I think he means it and we are so much happier although a small part of me feels that I have 'got my own way' like a spoilt child. I wonder if I sulked my way to winning? However it does occur to me now that I couldn't help but be depressed - I wasn't putting it on. It wasn't an issue that I would have broken up with dh over, and yet in some ways my behaviour was risking that.
(Sorry if this sounds ungrateful, but since we made the decision last Nov, I have discovered possible fertility problems that might make all of this academic anyway. I'm 37 - so don't hang around too long!!!)
Sorry if this a hopeless ramble, don't know if it will help or not...