What am I?

I start with “T”, ends with “T”, and within me is “T”. What am I?

Lighter than feather and softer than silk, yet the strongest man in the world cannot hold me for more than a few minutes. What am I?

Always old, sometimes new. Never sad, sometimes blue. Never empty, sometimes full. Never pushes, always pulls. What am I?

More rare today than long ago. There's a salutation from friends written below. What am I?

Riddles and Answers