I play with a fear of letting people down. That's what motivates me.
I would like to wish the England squad every success. I would also very much like to extend those wishes to Martin Johnson, Brian Smith, Mike Ford, John Wells, Graham Rowntree and the rest of the England 2011 World Cup management team who have been fantastic and deserve people to know that.
Right through to the end of the last World Cup game, I still couldn't bear the thought of not being perfect or letting people down.
I have no intention of letting this decision change the way that I approach my training and preparation for games, but the time has come for me to realise that I have gone as far as I can go with this England team.
What I am proud of is I have searched for the best of me and I have been a team man without fail.
I never ever believed that I would be able to give up on this dream which has driven me to live, breathe, love and embrace the game of rugby from the earliest days that I can remember.
Playing the game, representing the team, giving my all and never letting go has meant everything to me.
To say I have played through four World Cups, two Lions tours, 91 international games and a ridiculous number of injuries and other setbacks gives me an incredibly special feeling of fulfilment. I know myself well enough to know that I will never truly be satisfied.
I refuse to go into a fast-food outlet - to use the toilet even - in case anyone got the wrong idea and thought I was sneaking in a quick burger.
I do, have done and always will believe that I am very capable of performing and thriving at any level of the sport.