To be succinct, the biggest impact on work is the people. People will affect you regardless of if you are their manager or if you have a boss. Your co-workers can make you unhappy even if you love your line of work. How does one control this (if at all)?
Most of the time, one cannot. What can be controlled is the percentage of people disposed to certain personalities in each industry. Do as many power-hungry people exist in nursing as Wall St.? Probably not. Would engineers enjoy a conversation about travel as much as someone in sales? Probably not. Who do you like being around? Thankfully, there is some control... or else, I would go crazy.
In summary, people matter. You may play on the team, but remember the influence of your teammates, coach and even the fans. Your passion may not depend on them, but the fire can fuel or be burned out by them.
Thanks for reading and I pray that you were able to glean something from my writing!