In December, my niece Carrmen married her longtime boyfriend at a courthouse in Washington, D.C. It was the most heartfelt wedding I've been to in years, and as lovely as any big venue affair. I'm single, never-married and not even close to being engaged (um, I need a boyfriend first...thanks), but the experience inspired me to reconsider my would-be wedding options: Maybe a courthouse ceremony doesn't have to be the stepchild of nuptials. Maybe it's a rare opportunity to say, "Yes, we're…