Let me guess: You and your spouse - or perhaps your parents - are cousins?!
It won't be all that surprising - unfortunately - as a lot, and I mean a LOT, of people I know personally are married to their cousins. Some to their first cousins, even.
I mean, even I'd a crush on my first cousin, heh! But in my defense, I was 13 so... what did I know?
While sure, cousin marriages aren't exactly prohibited in Quran, nor Torah or Bible for that matter, but that doesn't change the fact that it's... well, incest. Besides, Islam suggests seeking life partners outside of your clan, just so the Muslims feel a stronger kinship towards each other.
Besides, inbreeding can be brutal to the offsprings with all sorts of birth defects. So, at the very least, think of the future generation.