I have heard, and I believe, that the amount of happiness in a person's life is directly related to the amount of control one feels they have over their life's events.

An athlete that has control over their position on their team or within their sport has direct influence over the outcomes. A lesser player with less say, less of a voice, has less control. I've been in both places, and I feel better when I'm in the control position, regardless the success of the team.

Outside of sports, we all have plenty of opportunities in daily life to take control of situations -- conscious effort will help us to recognize and take advantage of them.

"Where do you want to go for lunch?"
"What do you want to do?"
"What's your opinion?"

When faced with these open-ended-choice questions, offer an answer. Make it a habit. Note how you feel more in control and how the people around you look to you more for leadership -- even if it's just lunch plans (for now).