I finally got wise to the "you should smile more" thing; it showed me how I was coming across "out there" and I went and got counseling (because it matched how I was feeling inside, like not smiling!). I pay attention to what several different people say about me as it is a pretty good guide of what I maybe can't see about myself.
How do you feel/what do you "do" about those telling you to smile more? Have you tried consciously smiling more? It can literally change our mood:
http://www.time.com/time/health/arti...871687,00.html