Set your alarm to wake up early every day. Start the day with a good breakfast high in fibre, chase that with a strong coffee and go do something.
If you have absolutely nothing else to do, go to the gym, but doing it first thing could be hard on your back.
Definitely hit the gym every 2nd day. Force yourself. A half arsed workout will still cause a hormore release, which will help you come good again. Don't try to set any records in the gym until you feel 100%, just going there and getting a pump is enough.
Drink tons of water, eat a salad at least once a day, and hit the sack when you feel tired.
It will take a while to get out of what you're in, but doing someething like the above will help get you there.
Of course professional help... yada yada yada