The 'gone, gone [or dead, dead] and never called me mother' quote does indeed not appear in Mrs Wood's novel East Lynne, it probably appeared in some of the many stage adaptations. Wiki agrees with this ~~

"The much-"quoted" line "Gone! And never called me mother!" (variant: "Dead! Dead! And never called me mother!") does not appear in the book version of East Lynne. Both variants come from later stage adaptations."

It is, to be sure, in either variant, a fine dramatic line, to be spoken with staring eyes and clutched forehead.

~M~