Happiness is a choice and should not be dependent on a particular thing or any human.
The result generated from your actions and that of others should not determine your decision to be happy.
This life is too precious to allow things or human determine your happiness. It may be very difficult especially in business where result or profit is the major determinant of the whole staff.
Giving the key to your happiness to human or things is a sign that your happiness may last but a short while, because all things can never go the way you envisage them to go.
Humans will never toil through all the lanes you want to in order to make you happy. There will always be a comma somewhere to deny you Mr happiness.
So learn, teach yourself to base your happiness on nothing, let it be a confession that you will act out in your everyday adventures.
Lastly learn to celebrate your failures, it may look awkward but it really helps to relieve pain of disappointments and failures.