As far as the moms not apparently knowing one another; i.e., BD and MB, I am embarrassed to admit that I have lived here for 25 years (yes 25) and we live on 5-1/2 acres of land. I do not know ANY of my immediately surrounding neighbors. When we first moved here, my daughter was in 2nd grade. Part of our property is in the city (only a small portion) and the rest in the county. Our daughter (my baby girl) went to county schools. The next door neighbor had several children (some adopted and some biological) and they went to city schools. My husband gets out and about more than myself and has actually worked on fence posts, etc., with the man next door but I am embarrassed to day I hve NEVER met his wife. They are the only family who has been here the whole 25 years we have been here. I used to joke about this one house across the road from our house (we cannot even see it from our house). I used to say I thought it was a home for the witness protection program because we never saw a family move in and we never saw them move out. It was rental property at the time, but now is owned by a family "apparently with two small children". My husband has met and spoken to the couple a few times down at the mailbox, but again, I have never met them. We live 1 mile from a grocery store. It is weird to think I probably pass these folks in there A LOT and never have known it.
We were very active in the "rest of the community" and know/knew many of my daughter's friends parents through school activities, etc.