How long do you have to serve to fulfill your commitment? 4 years?
My advice is to serve your hitch and then get out. Who knows, you may change your mind again and make a career out of it.
As for repaying the debt, do not think minimize the difficulty of doing so, especially in this economy. Unless you are an electrical or chemical engineer, you may have trouble finding work. And if you don't want to feel like a slave, DO NOT incur student loan debt. Just ask one of the millions of unemployed college graduates who have Uncle Sam breathing down their backs.
As I said before, don't second guess yourself. The priest gave you good advice.