>>One sad experience that almost every Spaniard have to undergo in his life is when for first time a stranger young person address you using “usted”. You think “How a boy like me is using ‘usted’ when talking to me?. Or, maybe, I’m no longer a boy?”. <<

Juanmaria, I can sympathise! Somehow, somewhen, between visits to France, I graduated from being addressed by strangers as Mademoiselle to being Madame! Made me feel like I'd aged ten years, gone grey and put on forty pounds...

It didn't help that I had aged (some, but not ten) years, gone (a little, round the temples) grey and put on (some, not forty) pounds!