2003 TDI Beetle won't start in cold weather

Hi,

I have a 2003 TDI Beetle and its been experiencing some problems. I got the car from a family friend and this is the first diesel I've ever owned. From different advice I've got, I knew to be prepared for the cold Minnesota winters. I have been using the winter blend diesel gas (good for -40 below), using an additive, and have been turning the key several times before starting to get the glow plugs going. I've had to get the car jumped several times this past winter and today is the worst. 3 separate people have tried to help me.

After a 15 minute jump, the engine will chug-a-chug like its going to turn over but doesn't start. After 2 attempts, the battery is completely drained and required further charging. I was informed the battery was purchased less than a year ago. I have limited funds (student) so I need some good advice before I can go ahead with any mechanic decisions. Thanks to everyone!

How many miles are on the car?
Any check engine lights?
Have you change the fuel filter?

If the battery dies then there is an electrical drain somewhere. Common on older beetles is the rear hatch. It won't always close and the trunk light stays on.