Twilight lives long enough to see all of her friends to pass away within the short span of five months. Living an abnormally long amount for anypony to live, she faces hardships that nopony should have to face.
The Twilight that is in this story is not an alicorn, because if she was Longevity would be one of the advantages/disadvantages of being one, thus this story would make no sense.
Did spike orgasm or did scootaloo die?