guy I met can't have kids...

I've been recently dating this amazing guy I met. He treats me amazing and loves me so much and I love him and even though we haven't dated that long we've already talked about marriage. But the worst thing ever is that he told me he physically cannot have kids...there's something wrong with his sperm and the dr told him he can't have kids and he was born being infertile. I'm in my late 20s and looking for my future husband and I want to get married. But the thing I want the most is children and he can't give me that...I feel like a huge bitch for leaving the best guy I've met but I really want my own children with my future husband and I just don't know what to do and if it's worth ending it over....someone please help me !