You will be successful and productive only if you remain constant in your opinions. Think of your responsibilities over and over again, and stick up for your rights with passion. Change your environment, seek out new acquaintances and you will feel better.
Being emotionally rational won't lead you anywhere. Get rid of people who influence your personal life as soon as possible. Don't be overly polite and don't spoil your mood for anyone or anything.
Numbers: 4, 16, 37