Assuming this isn't clinical depression (others have advice on that), I'd recommend to take a close look at what your goals are. Basic philosophy: Don't make y

Assuming this isn't clinical depression (others have advice on that), I'd recommend to take a close look at what your goals are. Basic philosophy: Don't make your happiness dependent on things you can't control. In a large company, there are going to be a lot of things you can't control. Make your happiness dependent on things you can control, like how you spend your free time, how good a job you do at the stuff you do, and other things you individually can do to improve your future career mobility.