This is probably going to be completely unhelpful to you, but I recall this fic (with Amy/Rory as a base, but told via the Doctor to River)that has a post-BB storyline where Amy has parents and whether it's enough to help you or not you should read this anyway because it's wonderful :D http://wordmythology.livejournal.com/5012.html It is quite long though, so be prepared to need some time.

As to why would Amy put off the wedding? Hmmm ... let me think on that a bit. I have a niggle of an idea but it needs teasing out.