But Andy O'Brien is willing to talk about his.
Even still, the Vancouver Whitecaps defender's depression issues were not always well known — he was disowned by former club Leeds United before the truth came out.
"It was a learning experience," O'Brien said recently. "I'm probably one of the few people — footballers — to come out and say that they've suffered from (depression)."
Then Leeds manager Simon Grayson vowed that O'Brien, 33, would never play another game for the club again after he refused to take the pitch for a game against Burnley in November 2011.
But Leeds backtracked on its position after O'Brien, a dual English-Irish citizen who has played more than 300 matches in the English Premier League and represented Ireland in the 2002 World Cup, sought treatment at the Sporting Chance Clinic.
"We were exceptionally disappointed when Andy refused to play before the Burnley game and felt let down," Leeds said in a news release.
"It is now apparent that there were a number of issues that he was dealing with at that time which affected him in a way we could not imagine and he was not in a right state of mind to make such decisions."
While the Whitecaps have redeemed themselves from a last-place finish in their 2011 expansion to become the first Canadian team to qualify for the Major League Soccer playoffs, O'Brien has quietly earned some redemption of his own.
The second half of the MLS regular season marked the first time he has played regularly since his troubles became known.
Whitecaps coach Martin Rennie said the team based its decision to sign O'Brien mainly on his track record.
Rennie praised him for his steady play and his strong communication from central defence.
Vancouver captain Jay DeMerit, who plays alongside O'Brien also praised his communication skills and his steadying influence.
"He's brought what he was expected to bring to this team, some calmness, his communication, his organization at the back and just his solid defending," DeMerit said. "That's what someone like myself is there to do as well. So to partner up with him and really start to form a partnership, which we're doing, is great."
DeMerit said O'Brien's battles with health issues show his character.
"There's always ups and downs in your career," he said. "There's always ups and downs in every season that you're going to come through. You have to have that character to bounce back. You have to have that character to keep going — and Andy has that in abundance."
O'Brien was slated to start his fifth straight game Thursday for the Whitecaps against the Los Angeles Galaxy in a do-or-die playoff game worth a ticket to a two-game, total-goals series with the San Jose Earthquakes in the second round.
"It means everything to me," O'Brien of returning to the field on a consistent basis. "It's what you prepare for Monday to Friday. Football is a game about opinions and, sometimes, as hard as you work, you don't play. ... But all you can do is give yourself the best opportunity to (get in the lineup.)"
Although the Whitecaps came under heavy criticism for their lack of scoring down the stretch, O'Brien helped the defence stand out. The Whitecaps earned three shutouts — two from scoreless draws — in the four consecutive games that he started.
He joined the Whitecaps after obtaining his release from Leeds United just before an international transfer deadline closed in late July. After missing out on a pre-season in North America or abroad, he was sidelined briefly as a result of groin and knee troubles, but as the playoffs drew near, he felt settled in the lineup.
"I don't think I've strung (two games) together for a year," said O'Brien, who started seven of the eight regular-season games in which he appeared. "It could be 18 months. But I've picked up a niggling injury, but that's been dealt with, and I feel good."
Mentally as well as physically.
The deaths of NHLers Rick Rypien and Wade Belak, who suffered from depression have raised more awareness about illness among athletes.
O'Brien hopes that sharing his story will prompt others to come forward and get help.
"There is a bit of a stigma within football," said O'Brien. "It's a hard man's sport and what have you, but having come out and said that I have suffered from it, the amount of people that have spoken to me about footballers and ex-footballers, it's something that is out there. And, if I can offer any help, offer any sort of inspiration to anybody, it's something that I'm quite passionate about doing — possibly when I'm finished playing football — because I know from experience, being with other footballers for the past 18 years, people do suffer from time to time."
Often the symptoms are diverse and can vary on an individual basis.
"Depression, it's just a word, but there's a lot of things ingrained into that," he said. "That's just a word that is given to it, but you can suffer from a lot of things."
O'Brien credits strong support from his family with helping his through his troubles.
Now, regardless of Thursday's result, he looks forward to continuing his career after getting through a very difficult period.
"It's something that I've dealt with," O'Brien said. "I'm enjoying my football a lot more than I was doing, and that bodes well for the future."
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