What Happens?

One of the things I've noticed about youth ministry the longer I've done it has little to do with my experience as a youth worker, but alot to do with my friends and I as we've gotten older. I went to a high school with a strong FCA program and a bunch of kids who went to church every sunday. They were pretty serious about God. Now, we're all done with college and are young professionals in some capacity. Over 40% of the kids that I knew from North that were church kids have walked away. They still retain that oh so american Deism, but the worship of Jesus Christ has gone the way of the rest of their juvenile mis-conceptions about the world. So, the challenge lies in how we fix the problem. It is a little scary to know that all the labor, prayer and time I put into even our most committed students could stop in four short years. Are we presenting Christianity in an in accurate way? Are they just into church because it's a place their parents let them hang out with their friends? Do they just love God because of his stuff? I'm not sure what happens in between graduation from 12th grade and graduation from college. Maybe the lack of connection with other Christians in college? Maybe they get a little freedom from home, and find that sin is fun. (I know I did) I know that every single Christian will struggle and stray from Christ, but what can we do when they are young to make sure they come back?