To begin with, admitting that you don't admit something is not contradictory. It's much like saying 'If the instance should arise that I am confused, I will not admit it.' Look at it in this light. A proper young lady would never admit to passing gas when she was alone. It would be foolish to think that it doesn't happen, but she isn't going to volunteer that information. Granted, the same lady probably isn't likely to describe what it is like to pass gas, but she could. I may not admit to being confused, but it would be unrealistic to think that I have never been confused in the past.
As we live and grow, we change. Sooner or later, we will change in a way that we never expected. For some it is as simple as the little boy saying 'Girls are yukky' or 'I hate beans'. It can also be as complicated as falling in and out of love. 'I love you and I'll always be there for you' becomes 'I can't take it anymore, I'm out of here'.
In one form or another, we have all done it. We are all growing, learning, evolving humans and as long as we remain as such, we will continually contradict ourselves.