Everything? Sex? Naw. I don't buy it. I think from adolescence
  onwards, some people get 'stuck' in a repeating cycle of
  attempting to recreate the intensity of the sensations one had
  in the early onset of puberty, to relive the fantasyland
  sensation and confusion and control and resolution...

  ...but no, I don't think everything leads to sex or comes from
  sex.

  If it's your hobby, by all means. But, it's not everybody's
  hobby.