I have had a similar experience with my father's (COHEN/KISSIN) side of the family, in terms of having cousins close by that I never knew about.
After my parents were both gone (1997-98) I inherited letters from my father to my mother during WWII. In the course of reading them, I discovered that my father had stayed for a while with a cousin (on his mother's side) in a nearby town, but I never heard their names mentioned. The only cousins I knew about on my father's side were the sons of two of his sisters in New York.
I found out through persistent genealogical explorations (and dumb luck in a couple of cases) that my father's father had family living right next door to them in Brooklyn for a while, yet I was never told anything about this part of the family. And my grandfather Barnet Cohen had other brothers, one of whom settled in England. I was lucky enough to connect with that brother's descendants and have visited them a couple of years ago.
A family feud was apparently the cause of the Brooklyn disconnection, and possibly had bearing on why I never heard about the English side of the family, since they were friendly with the Brooklyn brother who was never mentioned.
So interesting, yet *so* frustrating!
Deb Cohen Skolnik
COHEN/KISSIN - Brooklyn/Vitebsk
SOLUTUCZKYN - Jahotyn/Jagotin/Yahotyn/Yagotin
GARBARCZ/GERBER - Mordy/Ostrow/Chicago
LANDE/LONDIN/LUNDIN - Bialystok