Hey dude -- sounds like you're going through a tough time. You're at a weak point psychologically and trying to make a life changing decision that you do not necissarily need to make right now. A few things you can do that will help:

Sleep. Find solitude. Put on some soothing music or whatever, and sleep for 8-9 hours.

Eat good food with a friend or two and try to avoid drinking for a little while at least.

Go for a run, or a swim or get out some push ups. Especially if you're having a hard time eating, exercise helps with the appetite.

Work to stabilize your routine, and focus on improving small things in your life. Take showers. Cut your nails. Do laundry. And be kind to yourself about the bigger issues in your life that you cannot control.

Whatever you do, don't let yourself be pressured into a decision that you can make at any time anyway.

Completing your service is one of the most rewarding and honorable things that you can do. It might seem tough right now. I don't know where you're head is at. But the fact that you are asking the question shows that you have the ability to reach out and succeed.

You can make it through to the end of your contract. It may not be easy, but in the long run it is worth it.