He thought he had it figured out. Serve his time, go home the first chance he gets and then life out the future Buffy warned him about - saving the world, dying a hero. It seemed like a good idea but now that the time has come, he's not so sure about that anymore. He's a different man than when he first arrived. Things have changed so much he hardly recognizes the person he was back then.
So, he does what he always does when he's at a loss: smokes and makes his way slowly through the whiskey bottles he brought along. Play nice and you too can have some liquid courage. ]