What I think is, it's a mistake to portray yourself as invincible. I know it's required in a lot of careers. You have to look good, sound good. You need to make people think you're competent. More than that, you need them to think that you're the best, that you've got a lot of potential and you're going to reach its maximum. You've got your act together, you're going places, you're dependable, you're intelligent, you know what you're doing.
The trouble is, you learn this behavior so well, that it bleeds over into your social relationships, too. Maybe the bleed is obligatory--if you're dedicated to your job, chances are good it forms the basis of social life. Your friends are also your co-workers and colleagues. At work, you've got them believing you can accomplish anything. At play, won't they have those same expectations?
But what happens if you're not invincible away from the office, when you don't have the answers, when something gives way in your personal life? Who is going to help you? All those co-workers who think you're dialed in? Are they going to believe that you've got problems? Are they going to hear what you're saying and take action, or will they just brush it off, figuring you can handle it as well as you handle the pressures of work?
Don't act invincible, because you're not. Someday you're going to need someone to believe in your pain, and if you've spent your entire life convincing people it doesn't exist, you're going to look like the boy who cried wolf. Trust me. You're not doing yourself any favors by letting people preserve the illusion of your perfection. You're going to need their help, so try not to play the game so well they won't be able to offer it.