In high school, it was not being included that hurt the most. It was alienating, occasionally unbearable, and generally awful. It didn't happen to me all the time, but often enough (maybe to everyone, I can't speak to that), that I can remember that feeling and yes, it does compare to other hurtful things now. Eventually it became a kindness not to be invited to all the parties and events, but other things (that used to not matter) have become dreadful.
When my 10th grade English teacher returned an essay on Copernicus blanketed in red, it might have caused a twinge (I had a *little* pride), but it was not crushing. Now, though, I am atomized by that sense of 'not good enough'. It is devastating to get back a draft copy bleeding in corrections (and suggestions). In fact, it's wretched even knowing my writing doesn't make me proud, even before it goes to a reader! It can be paralyzing - that fear of that humiliation.
Thus, the edit.
This part of the writing processes is considerably more painful that the word dump, which (barring writer's block) most people enjoy. In nearly all circumstances, it is imperative to go through your work many times wearing many hats, with many combs of varied tooth-sizes. Editing will certainly improve your piece, hopefully coalescing your intention, deepening your plot and characters, and excising extraneous verbiage. It will help to snap it together to be exactly what it should be, concise, inspiring, and your best effort.
Editing is hard, lonely, and menial: it is the doxie-fighting role in fighting off the bad wizard. Stick with it, though, for this is what will make your product irresistible!