I would be the poster boy for the sensitive and overthinkers club I would suggest. An old coach used to say to us "over analyais causes paralysis." He was speaking in a sporting context, but I remind myself of it when I am overdoing it in every day situations.
I have often envyed those who can brush things off so easily also, how easy would things be if you just didn't give a fuck? But have also wondered as you have whether they feel the highs as I do as well.

I eagerly await your story, does it involve a Japanese girl as well? They seem to have quite a habit of appearing in these kind of dramas!