Now what...

Last night I found out he actually doesn't want anymore children... he has 2 from a previous marriage, I have none..

he can actually no longer have children. I have known this since we started dating, but early on it was discussed that, there are options (reversal, at home insemination) and he'd be willing to try other resources. So about a year ago, we tried at home insemination.. after months of failure, I stopped trying because everytime it failed I would become extremely depressed for days. Then last night at dinner, I told him in the next few months, I'd like to try again. His silence was enough for me to know something was wrong. we talked, he said how watching me get upset was heart breaking for him, && then he told me, ever since we have gotten our puppy, he realized he does not want more children. Having our dog reminded him what it was like to have a baby. And he said it's not what he wants..

This clearly is a long story short. But I need some advice... I am so lost, sad, hurt.. our relationship is great otherwise... we've been together for a little over three years. (Live together)