Yeah, read it, along with other works by Sartre, Camus, all the way down to Kierkergaard and earlier examples of this line of thinking (note: European and older, so those works were like Star Wars movies to us at the time, in the sense that everybody read them, not just students dressed in black).

The "Existentialism is a Humanism" presents a more "heroic" outlook of the matter, associated with Sartre's engagement with politics at the time. Even so it deals with anxiety, lack of values, etc. That "in fashioning himself, fashions man" only works as an encouragement if you also believe that people everywhere in large quantities are fashioning the world for the better (as Sartre did with regards to communism).

But for the more bleak outlook that is quite more common, you can read Sartre's own "Nausea" to see how the ideas as described in "E.I.A.H" can play into everyday life. Even the title of the novel ("sea sickness" -- meant about the absurdity of life, is telling). The angst/anxiety etc. is more often than not present without any conveniently comforting heroic ideas of self-fashioning, like in the end of the book, or in E.I.A.H.

I suspect that angst stems largely from loss of faith. Whether it's faith in some religion, or faith in some ideology. I rejected faith very early, and so lack of inherent meaning doesn't occur as bleak. It's just what's so. And it's arguably all about selection.