They touched on the repercussions when Mephisto was all, "Ha ha, now the daughter you would have had with Mary Jane will never be born." (Giving Spider-Girl fans something else to be bitter about.) And apparently parts of their souls will be screaming for eternity for the great love they have lost, but well, you aren't going to see that any time soon.
And for such a "young" guy, Spider-Man has a lot of dead/erased-from-the-timeline kids.