And I always tell folks that if you can afford to take a few weeks/months off, do take it out and travel. It doesn't need to be a fancy, expensive vacation to the other side of the globe. But as long as it's forcing you into an environment that is unfamiliar, where things like food, culture and even basic human interactions are so different to what you are familiar with, you'll realise how quickly your energies get replenished and the problems/envy/lack of ambition will all start feeling small in the rear view mirror.
As the saying goes, it's just a bad day, not a bad life. :)