Who is Alexandrina Tyler from Schismatrix Plus and what is their importance?

Alexandrina was Lindsay's first wife. Originally from The Republic of Mare Serenitatis, Alexandrina is Lindsay's mother's cousin. She lost her citizenship during the Shaper purges fifty years before, but she never forgot her home. Alexandrina later becomes reacquainted with Lindsay and he offers her a job managing his home. Over time, she becomes the curator of a museum created on the old Tyler mansion that is dedicated to preserving what is left of their old ways of life.