" smoking weed," -- bad advice.
(inb4 hate from weed loves - a befuddled brain does not help people face and resolve issues. Also for some people weed can amplify your current mood, not a good bet for the OP. Thirdly, smoking is just very very bad for the health).
Here's what you should do: work fewer hours. E.g. if you're slamming 12 hours per day, cut it back to 6 or something. Spend those other hours away from your PC doing something relaxing even watching a DVD helps - the best bet, as others have mentioned, is some exercise, if that's possible where you live.
If that's not possible, check-out some Aria pics: