Wishes and Book Characters

Way back in the last millennium, I went to my first writer's conference. It was a looong time ago (maybe 15 years), but I remember it, especially the "first book" panel discussion.  As an unpublished writer and newbie, listening to the journeys of other writers was inspiring. But mostly I remember sitting in the crowded room wishing.  And dreaming. And hoping that one day, I'd get to talk about my own first book.
So tomorrow, my wish comes true.  I'm on a panel called "First Crop: Planting an Idea, Harvesting a Book" with YA author Jennifer R Hubbard (The Secret Year) and PB author Jeannine Norris (Tonight, You Are My Baby).  Btw, we're part of a really fun group of authors/illustrators called the KidLit Authors Club  
It's time for true confessions. I've never been to Philadelphia. Why, yes, I do live closer to that city than I do to any other city in the USA. As a long time New Yorker I still have that mentality that "the city" means NYC.  In my defense, I have friends and family in the NYC area. (It's a paltry defense, but it's all I have)
Yeah. I'm jumping up and down again. I'm really excited about the weekend.
But here's the other thing. My book characters in my w.i.p. have decided to start talking to me.  Finally!! And I'm experiencing that wonderful feeling of being torn between real life and my writing life. 
It happens when I'm in the middle of a story.  No matter what's going on in my real life, I find myself pulled into another world.
When you write, how do you leave your characters behind? 
It's hard for me. Even when I'm having a dream-come-true  moment, I can't let them go. Besides thinking about what they'd do in their own world, I start wondering what my characters would think if they were in mine. Would they like the library where I work?  My favorite view of the Barnegat Bay? And what would they think of Philadelphia?
I guess I'll find out the Philly answer soon.  It's time to get all of us into the car and hit the road.