ready to play

My friend quoted this recently from a book by Richard Rosen:

"...to be playful is not to be trivial or frivolous, or to act as if nothing of consequence will happen.

On the contrary, when we are playful with each other we relate as free persons, and the relationship is open to surprise; everything that happens is of consequence, for seriousness is a dread of the unpredictable outcome of open possibility."

My friend was asking what role play has in your life, and my question is, why so serious? Why do some people fear the unpredictable?
I have never been afraid of surprise, in fact, I think I can honestly say that lack of surprise may be the reason why most relationships in my life have ended when they've ended, why I've moved on, why I look for new interests, new people, new ideas, new answers. There's something infinitely intriguing to me about the thing I don't know, the sensation I haven't felt, the restaurant I haven't eaten in, the activity I've never tried, the person I can't completely fathom. When things become predictable, there's a spark that is lost. Yes, it's nice to know that someone loves you and will be there to hold your hand, but for me there's also that need for that other person to for no apparent reason, shove me into a snow bank, or show up at my door and kiss me like the world is about to end, then turn around and walk off. Life doesn't make sense, it's messy and stupid and beautiful and nonlinear in so many ways, and we are always changing, reinventing, learning, making mistakes, becoming things we weren't yesterday, a week ago, a year ago. It's never safe, even if you don't change, everything around you will.
So why so serious? Why can't everyone play and forgive and live with the unpredictable and just enjoy it while it's there and start over and over, opening ourselves up to as much as we can swallow?
I love that moment when someone says something and you burst out laughing because it's exactly what you weren't expecting. And as amazing as a moment like that is, sometimes you have to steel yourself for a consequence you didn't want, but just happens.
I need a few more do-overs, a few more chances, a few more shoves into a snow bank.
Oh god, I'm making no sense - bed!