And not being mean to you, but you weren't The One. If you had been, no children would have been fine with him. In this case, it's a convenient out.
Annoying, yes, but 12 weeks is hardly the end of the world. Better 12 weeks than 2 years. Or as it was in my case, almost 4 years.
Now that I've had a few days to think about it, I'm actually glad he broke up with me. He was such a nice guy, and I felt comfortable with him. But our lifestyles definitely do not match up in many ways, and I kind of blocked them out just cuz he was so nice. I don't think the relationship would've lasted too long anyway.